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Chapter 1 The Internet is a worldwide, publicly accessible series of interconnected computer networks that transmit data by packet switching using the standard Internet Protocol (IP). It is a "network of networks" that consists of millions of smaller domestic, academic, business, and government networks, which together carry various information and services, such as electronic mail, online chat, file transfer, and the interlinked Web pages and other documents of the World Wide Web.

The name Internet Internet is traditionally written with a capital first letter, as it is a proper noun. The Internet Society, the Internet Engineering Task Force, the Internet Corporation for Assigned Names and Numbers, the World Wide Web Consortium, and several other Internet-related organizations use this convention in their publications. Many newspapers, newswires, periodicals, and technical journals capitalize the term (Internet). Examples include The New York Times, the Associated Press, Time, The Times of India, Hindustan Times, and Communications of the ACM. Others assert that the first letter should be in lower case (internet), and that the specific article “the” is sufficient to distinguish “the internet” from other internets. A significant number of publications use this form, including The Economist, the Canadian Broadcasting Corporation, the Financial Times, The Guardian, The Times, and The Sydney Morning Herald. As of 2005, many publications using internet appear to be located outside of North America—although one U.S. news source, Wired News, has adopted the lower-case spelling.

Historically, Internet and internet have had different meanings, with internet meaning “an interconnected set of distinct networks,” and Internet referring to the world-wide, publicly-available IP internet. Under this distinction, "the Internet" is the familiar network via which websites exist, however "an internet" can exist between any two remote locations. Any group of distinct networks connected together is an internet; each of these networks may or may not be part of the Internet. The distinction was evident in many RFCs, books, and articles from the 1980s and early 1990s (some of which, such as RFC 1918, refer to "internets" in the plural), but has recently fallen into disuse. Instead, the term intranet is generally used for private networks. See also: extranet. Some people use the lower-case term as a medium (like radio or newspaper, e.g. I've found it on the internet), and first letter capitalized as the global network.

History of the Internet In the fifties and early sixties, prior to the widespread inter-networking that led to the Internet, most communication networks were limited by their nature to only allow communications between the stations on the network. Some networks had gateways or bridges between them, but these bridges were often limited or built specifically for a single use. One prevalent computer networking method was based on the central mainframe method, simply allowing its terminals to be connected via long leased lines. This method was used in the 1950s by Project RAND to support researchers such as Herbert Simon, in Pittsburgh, Pennsylvania, when collaborating across the continent with researchers in Santa Monica, California, on automated theorem proving and artificial intelligence.

Creation The USSR's launch of Sputnik spurred the United States to create the Advanced Research Projects Agency, known as ARPA, in February 1958 to regain a technological lead.[1][2] ARPA created the Information Processing Technology Office (IPTO) to further the research of the Semi Automatic Ground Environment

(SAGE) program, which had networked country-wide radar systems together for the first time. J. C. R. Licklider was selected to head the IPTO, and saw universal networking as a potential unifying human revolution. Licklider moved from the Psycho-Acoustic Laboratory at Harvard University to MIT in 1950, after becoming interested in information technology. At MIT, he served on a committee that established Lincoln Laboratory and worked on the SAGE project. In 1957 he became a Vice President at BBN, where he bought the first production PDP-1 computer and conducted the first public demonstration of time-sharing. At the IPTO, Licklider recruited Lawrence Roberts to head a project to implement a network, and Roberts based the technology on the work of Paul Baran, who had written an exhaustive study for the U.S. Air Force that recommended packet switching (as opposed to circuit switching) to make a network highly robust and survivable. After much work, the first two nodes of what would become the ARPANET were interconnected between UCLA and SRI International in Menlo Park, California, on October 29, 1969. The ARPANET was one of the "eve" networks of today's Internet. Following on from the demonstration that packet switching worked on the ARPANET, the British Post Office, Telenet, DATAPAC and TRANSPAC collaborated to create the first international packet switched network service. In the UK, this was referred to as the International Packet Stream Service (IPSS), in 1978. The collection of X.25-based networks grew from Europe and the US to cover Canada, Hong Kong and Australia by 1981. The X.25 packet switching standard was developed in the CCITT (now called ITU-T) around 1976. There were independent of the TCP/IP protocols that arose from the experimental work of DARPA on the ARPANET, Packet Radio Net and Packet Satellite Net during the same time period. Vinton Cerf and Robert Kahn developed the first description of the TCP protocols during 1973 and published a paper on the subject in May 1974. Use of the term "Internet" to describe a single global TCP/IP network originated in December 1974 with the publication of RFC 674, the first full specification of TCP that was written by Vinton Cerf, Yogen Dalal and Carl Sunshine then at Stanford University. During the next nine years, work proceeded to refine the protocols and to implement them on a wide range of operating systems. The first TCP/IP-wide area network was made operational by January 1, 1983 when all hosts on the ARPANET were switched over from the older NCP protocols to TCP/IP. In 1985, the United States' National Science Foundation (NSF) commissioned the construction of a university 56 kilobit/second network backbone using computers called "fuzzballs" by their inventor, David Mills. The following year, NSF sponsored the development of a higher speed 1.5 megabit/second backbone that become the NSFNet. A key decision to

use the DARPA TCP/IP protocols was made by Dennis Jennings, then in charge of the Supercomputer program at NSF. The opening of the network to commercial interests began in 1988. The US Federal Networking Council approved the interconnection of the NSFNET to the commercial MCI Mail system in that year and the link was made in the summer of 1989. Other commercial electronic email services were soon connected, including OnTyme, Telemail and Compuserve. In that same year, three commercial Internet Service Providers were created: UUNET, PSINET and CERFNET. Important, separate networks that offered gateways into, then later merged with the Internet include Usenet and BITNET. Various other commercial and educational networks, such as Telenet, Tymnet, Compuserve and JANET were interconnected with the growing Internet. Telenet (later called Sprintnet) was a large privately-funded national computer network with free dial-up access in cities throughout the U.S. that had been in operation since the 1970s. This network was eventually interconnected with the others in the 1980s as the TCP/IP protocol became increasingly popular. The ability of TCP/IP to work over virtually any pre-existing communication networks allowed for a great ease of growth although the rapid growth of the Internet was due primarily to the availability of commercial routers from companies such as Cisco Systems, Proteon and Juniper, the availability of commercial Ethernet equipment for local area networking and the widespread implementation of TCP/IP on the UNIX operating system.

Growth The network gained a public face in the 1990s. On August 6, 1991, CERN, which straddles the border between France and Switzerland, publicized the new World Wide Web project, two years after British scientist Tim Berners-Lee had begun creating HTML, HTTP and the first few Web pages at CERN. An early popular web browser was ViolaWWW based upon HyperCard. It was eventually replaced in popularity by the Mosaic web browser. In 1993 the National Center for Supercomputing Applications at the University of Illinois released version 1.0 of Mosaic, and by late 1994 there was growing public interest in the previously academic/technical Internet. By 1996 usage of the word "Internet" had become commonplace, and consequently, so had its misusage as a reference to the World Wide Web.

Meanwhile, over the course of the decade, the Internet successfully accommodated the majority of previously existing public computer networks (although some networks, such as FidoNet, have remained separate) During the 1990s, it was estimated that the Internet grew by 100% per year, with a brief period of explosive growth in 1996 and 1997. This growth is often attributed to the lack of central administration, which allows organic growth of the network, as well as the non-proprietary open nature of the Internet protocols, which encourages vendor interoperability and prevents any one company from exerting too much control over the network.

Today's Internet Aside from the complex physical connections that make up its infrastructure, the Internet is facilitated by bi- or multi-lateral commercial contracts (e.g., peering agreements), and by technical specifications or protocols that describe how to exchange data over the network. Indeed, the Internet is essentially defined by its interconnections and routing policies. As of June 10, 2007, 1.133 billion people use the Internet according to Internet World Stats. Writing in the Harvard International Review, philosopher N.J.Slabbert, a writer on policy issues for the Washington DC-

based Urban Land Institute, has asserted that the Internet is fast becoming a basic feature of global civilization, so that what has traditionally been called "civil society" is now becoming identical with information technology society as defined by Internet use.

Worksheet Activity #1 How does internet become popular? List down the people who are involved in developing internet.

Chapter 2 Terminology: Internet vs. World Wide Web The Internet and the World Wide Web are not synonymous. The Internet is a collection of interconnected computer networks, linked by copper wires, fiber-optic cables, wireless connections, etc. In contrast, the Web is a collection of interconnected documents and other resources, linked by hyperlinks and URLs. The World Wide Web is one of the services accessible via the Internet, along with many others including e-mail, file sharing and others described below. The Internet protocol suite is a collection of standards and protocols organized into layers so that each layer provides the foundation and the services required by the layer above. In this scheme, the Internet consists of the computers and networks that handle Internet Protocol (IP) data packets. Transmission Control Protocol (TCP) depends on IP and solves problems like data packets arriving out of order or not at all. Next comes Hypertext Transfer Protocol (HTTP), which is an application layer protocol. It runs on top of TCP/IP and provides user agents, such as web browsers, with access to the files, documents and other resources of the World Wide Web.

Common uses of the Internet E-mail

The concept of sending electronic text messages between parties in a way analogous to mailing letters or memos predates the creation of the Internet. Even today it can be important to distinguish between Internet and internal e-mail systems. Internet e-mail may travel and be stored unencrypted on many other networks and machines out of both the sender's and the recipient's control. During this time it is quite possible for the content to be read and even tampered with by third parties, if anyone considers it important enough. Purely internal or intranet mail systems, where the information never leaves the corporate or organization's network, are much more secure, although in any organization there will be IT and other personnel whose job may involve monitoring, and occasionally accessing, the email of other employees not addressed to them.

The World Wide Web Many people use the terms Internet and World Wide Web (or just the Web) interchangeably, but, as discussed above, the two terms are not synonymous. The World Wide Web is a huge set of interlinked documents, images and other resources, linked by hyperlinks and URLs. These hyperlinks and URLs allow the web-servers and other machines that store originals, and cached copies, of these resources to deliver them as required using HTTP. HTTP is only one of the communication protocols used on the Internet.

Graphic representation of less than 0.0001% of the WWW, representing some of the hyperlinks

Web services also use HTTP to allow software systems to communicate in order to share and exchange business logic and data. Software products that can access the resources of the Web are correctly termed user agents. In normal use, Web browsers, such as Internet Explorer and Firefox access Web pages and allow users to navigate from one to another via hyperlinks. Web documents may contain almost any combination of

computer data including photographs, graphics, sounds, text, video, multimedia and interactive content including games, office applications and scientific demonstrations. Through keyword-driven Internet research using search engines, like Yahoo!, and Google, millions of people worldwide have easy, instant access to a vast and diverse amount of online information. Compared to encyclopedias and traditional libraries, the World Wide Web has enabled a sudden and extreme decentralization of information and data. It is also easier using the Web than ever before for individuals and organizations to publish ideas and information to an extremely large audience. Anyone can find ways to publish a web page or build a website for very little initial cost. Publishing and maintaining large, professional websites full of attractive, diverse and up-to-date information is still a difficult and expensive proposition, however. Many individuals and some companies and groups use "Web logs" or blogs, which are largely used as easily-updatable online diaries. Some commercial organizations encourage staff to fill them with advice on their areas of specialization in the hope that visitors will be impressed by the expert knowledge and free information, and be attracted to the corporation as a result. One example of this practice is Microsoft, whose product developers publish their personal blogs in order to pique the public's interest in their work. Collections of personal Web pages published by large service providers remain popular, and have become increasingly sophisticated. Whereas operations such as Angelfire and GeoCities have existed since the early days of the Web, newer offerings from, for example, Facebook and MySpace currently have large followings. These operations often brand themselves as social network services rather than simply as Web page hosts. Advertising on popular Web pages can be lucrative, and e-commerce or the sale of products and services directly via the Web continues to grow. In the early days, Web pages were usually created as sets of complete and isolated HTML text files stored on a Web server. More recently, Web sites are more often created using content management system (CMS) software with, initially, very little content. Users of the CMS, who may be paid staff, members of a club or other organization, or even members of the public, fill the CMS database with content using editing pages designed for that purpose, while casual visitors view and read this content in its final HTML form.

There may or may not be editorial, approval and security systems built into the process of taking newly entered content and making it available to the target visitors.

Common search engines Google Google is the world's most popular search engine. It began as a search project in 1996 by Larry Page and Sergey Brin, who were two Ph.D. students at Stanford University. They developed a search engine algorithm that ranked Web pages not just by content and keywords, but by how many other Web pages linked to each page. This strategy produced more useful results than other search engines, and led to a rapid increase in Google's Web search marketshare. The Google ranking algorithm was later named "PageRank" and was patented in September of 2001. In only a short time, Google became the number one search engine in the world.

According to Google's website, the company's mission is to "organize the world's information and make it universally accessible and useful." While the Web search remains Google's primary tool for helping users access information, the company offers several other services as well. Some of these include: • • • • • • • • • •

Froogle - price comparison shopping Image Search - search for images on the Web Google Groups - online discussion forums Google Answers - answers to questions based on a bidding system Google Maps - maps and directions Google Toolbar - a downloadable search tool Blogger - a free blogging service Gmail - Web-based e-mail with several gigabytes of storage AdWords - Advertising services for advertisers AdSense - Advertising services for Web publishers

Google has become such a popular search engine that the term "Google" is now often used as a verb, synonymous with "search." For example, if you are looking for information about someone, you can Google that person using Google's search engine.

Yahoo! Yahoo! is one of the Internet's leading search engines. It is also the largest Web portal, providing links to thousands of other websites. These links include sites from the Yahoo! Directory as well as news stories that are updated several times a day. Besides being a portal and search engine, Yahoo! offers several other services as well. Some of these services include: • • • •

Yahoo! Yahoo! Yahoo! Yahoo!

Finance - stock quotes and financial information Shopping - online retail and price comparison services Games - online games playable over the Internet Groups - organized discussions among Internet users

• • • •

Yahoo! Yahoo! Yahoo! Yahoo!

Travel - travel information and booking services Maps - maps and directions Messenger - instant messaging Mail - free Web-based e-mail

Live Search -(formerly Windows Live Search) is the name of Microsoft's web search engine, successor to MSN Search, designed to compete with the industry leaders Google and Yahoo!. Live Search is accessible through Microsoft's Live.com and MSN web portal. The new search engine offers some innovative features, such as the ability to view additional search results on the same web page (instead of needing to click through to subsequent search result pages) and the ability to dynamically adjust the amount of information displayed for each search-result (i.e. just the title, a short summary, or a longer summary). It also allows the user to save searches and see them updated automatically on Live.com.

Ask.com -is an Internet search engine. It is also the company name of the division of IAC Search & Media, founded in 1996 by Garrett Gruener and David Warthen in Berkeley, California. The original software was implemented by Gary Chevsky from his own design. Three venture capital firms, Highland Capital, Institutional Venture Partners, and The RODA Group were early investors.

Infoseek -was a very popular search engine founded in 1994 by Steve Kirsch, et al. By September 1997 it boasted 7.3 million visitors per month. It was bought by Disney in 1998, and the technology was merged with that of the Disney-acquired Starwave to form the Go.com network. Since then it has been replaced with Yahoo! search and is no longer in use.

Infoseek featured a very complex system of search modifiers, including boolean modifiers such as the most basic "OR" and "NOT", up to parentheses and quotes, up to being able to say that you want one word or phrase to appear within x number of words from another word or phrase. Infoseek was also known as "big yellow". Before being bought by Disney, Infoseek also offered a free webhosting package that was better than many of today's offerings. It was free of advertising, and had apparently no limits on the amount of webspace that could be used. After being purchased by Disney and converted to the Go Network (and then Go.com because of trademark disputes with competitor, Goto.com), large, cumbersome ads started appearing on every page hosted. In February 2001, Disney made the decision to cancel the service and layoff the entire staff. Eventually, the webhosting service disappeared entirely, virtually overnight, with little or no warning. In 2001 Bernt Wahl, Andy Bensky and 15 software engineers -- Infoseek employees -- led a management buyout attempt from Disney. Infoseek's Ultraseek Server software technology, an enterprise search engine product, was sold in 2000 to Inktomi. Under Inktomi, Ultraseek Server was renamed "Inktomi Enterprise Search". In December 2002 (prior to Yahoo's acquisition of Inktomi), the Ultraseek product suite was sold to a competitor Verity Inc, who re-established the Ultraseek brand name and continued development of the product. In December 2005, Verity was acquired by UK company Autonomy PLC. Under Autonomy, Ultraseek continues to be actively developed and marketed as Autonomy's entry-level keyword-based site search offering. Today, "infoseek.com" now forwards to the "go.com" website. The brand name of Infoseek is now completely unused in North America, however Infoseek Japan still operates.

AltaVista -was started by Digital Equipment Corporation employee volunteers who were trying to provide services to make finding files on the public network easier. AltaVista was launched public as an internet search engine on 15 December 1995 at http://altavista.digital.com.

At launch the service had two innovations that set it ahead of the other search engines. It used a fast multithreaded crawler (Scooter) that could cover a lot more Web pages than were believed to exist, and an efficient search back-end running on advanced hardware; as of 1998, 20 multi-processor machines using DEC's then-new Alpha processor, along with 130GB RAM and 500GB hard disk space each, receiving 13 million queries per day. These made AltaVista the first searchable, full-text database of a large part of the World Wide Web.

Excite -is an Internet portal, and as one of the pioneering "dotcoms" of the 1990s (along with Yahoo! and Netscape), was once one of the most recognized brands on the Internet. Excite offers a variety of services, including search, web-based email, instant messaging, stock quotes, and a customizable user homepage. The content is collated from over 100 different sources.

Lycos -is a search engine and web portal centered around broadband entertainment content. It began as a search engine research project by Dr. Michael Loren Mauldin of Carnegie Mellon University in 1994. It was incorporated in 1995 and went on to become one of the most visited online destinations in the world with a global presence in more than 40 countries. Lycos merged with Terra Networks of Spain in May of 2000, forming a new company, Terra Lycos, creating one of the world's largest Internet companies. In Oct. 2004, Lycos was sold a second time to Daum Communications Corporation, the 2nd largest Internet portal in Korea, becoming Lycos, Inc. Lycos remains a top 25 Internet destination in the US, and the 13th largest online property worldwide according to comScore Media Metrix. Lycos also remains a top 5 Internet portal, behind Yahoo, MSN, AOL and MySpace (comScore Media Metrix).

Worksheet Activity #2 List down other search engines that are uncommonly cited. Discuss why are these search engines are not commonly cited.

Chapter 3 Internet basic terms E-mail It's hard to remember what our lives were like without e-mail. Ranking up there with the Web as one of the most useful features of the Internet, e-mail has become one of today's standard means of communication. Billions of messages are sent each year. If you're like most people these days, you probably have more than one e-mail address. After all, the more addresses you have, the more sophisticated you look... E-mail is part of the standard TCP/IP set of protocols. Sending messages is typically done by SMTP (Simple Mail Transfer Protocol) and receiving messages is handled by POP3 (Post Office Protocol 3), or IMAP (Internet Message Access Protocol). IMAP is the newer protocol, allowing you to view and sort messages on the mail server, without downloading them to your hard drive. Though e-mail was originally developed for sending simple text messages, it has become more robust in the last few years. Now, HTML-based e-mail can use the same code as Web pages to incorporate formatted text, colors, and images into the message. Also, documents can be attached to e-mail messages, allowing files to be transfered via the e-mail protocol. However, since e-mail was not originally designed to handle large file

transfers, transferring large documents (over 3 MB, for example) is not allowed by most mail servers. So remember to keep your attachments small!

Blog Short for "Web Log," this term refers to a list of journal entries posted on a Web page. Anybody who knows how to create and publish a Web page can publish their own blog. Some Web hosts have made it even easier by creating an interface where users can simply type a text entry and hit "publish" to publish their blog. Because of the simplicity of creating a blog, many people (often young kids and adults) have found a new presence on the Web. Instead of writing confidential entries in a book that no one is supposed to see, people now can share their personal feelings and experiences with thousands of people around the world. Blogs are typically updated daily, monthly, or anywhere in between. "Blog" may also be used as a verb, as in "Wow, Matt sure blogged a lot last week."

Download This is the process in which data is sent to your computer. Whenever you receive information from the Internet, you are downloading it to your computer. For example, you might have to download an upgrade for your computer's operating system in order to play a new game (especially if you're using Windows). Or you might download a demo version of a program you are thinking about buying from the software company's Web site. The opposite of this process, sending information to another computer, is called uploading.

Emoticons These are the little text-based faces and objects that you often see in e-mail and online chat. They help give the reader a sense of the writer's feelings behind the text. For example, the classic =) face shows that the writer is happy about something or that his message in good humor. The =P face is used to show

frustration or to say "Whatever..." Emoticons can also be used to create real-world objects. For example, a @-->-->--- is supposed to be a long-stemmed rose, which you can use to show affection. Though I think most women would prefer a real long-stemmed rose if they had a choice.

Homepage This is the starting point or front page of a Web site. This page usually has some sort of table of contents on it and often describes the purpose of the site. For example, http://www.apple.com/index.html is the home page of Apple.com. When you type in a basic URL, such as "http://www.cnet.com," you are typically directed to the home page of the Web site. Many people have a "personal home page," which is another way the term "home page" can be used.

HTML (Hyper-Text Markup Language) Stands for "Hyper-Text Markup Language." This is the language that Web pages are written in. Also known as hypertext documents, Web pages must conform to the rules of HTML in order to be displayed correctly in a Web browser. The HTML syntax is based on a list of tags that describe the page's format and what is displayed on the Web page. Fortunately, the HTML language is relatively easy to learn. Even more fortunately (so much for good grammar), many Web development programs allow you to create Web pages using a graphical interface. These programs allow you to place objects and text on the page and the HTML code is written for you.

HTTP (HyperText Transfer Protocol) Stands for "HyperText Transfer Protocol." This is the protocol used to transfer data over the World Wide Web. That's why all Web site addresses begin with "http://". Whenever you type a URL into your browser and hit Enter, your computer sends an HTTP request to the appropriate Web server. The Web server, which is designed to handle HTTP requests, then sends to you the requested HTML page.

Hyperlink A hyperlink is a word, phrase, or image that you can click on to jump to a new document or a new section within the current document. Hyperlinks are found in nearly all Web pages, allowing users to click their way from page to page. Text hyperlinks are often blue and underlined, but don't have to be. When you move the cursor over a hyperlink, whether it is text or an image, the arrow should change to a small hand pointing at the link. When you click it, a new page or place in the current page will open. Hyperlinks, often referred to as just "links," are common in Web pages, but can be found in other hypertext documents. These include certain encyclopedias, glossaries, dictionaries, and other references that use hyperlinks. The links act the same way as they do on the Web, allowing the user to jump from page to page. Basically, hyperlinks allow people to browse information at hyperspeed.

Link When you are browsing the Web and you see a highlighted and underlined word or phrase on a page, there is a good chance you are looking at a link. By clicking on a link, you can "jump" to a new Web page or a completely different Web site. While text links are typically blue and underlined, they can be any color and don't have to be underlined. Images can also serve as links to other Web pages. When you move the cursor over a link in a Web page, the arrow will turn into a little hand, letting you know that it is a link. The term "hypertext" comes from the way links can quickly send you to another Web destination.

Search Engine Google, Excite, Lycos, AltaVista, Infoseek, and Yahoo are all search engines. They index millions of sites on the Web, so that Web surfers like you and me can easily find Web sites with the information we want. By creating indexes, or large databases of Web sites (based on titles, keywords, and the text in the pages), search engines can locate relevant Web sites when users enter search terms or phrases. When you

are looking for something using a search engine, it is a good idea to use words like AND, OR, and NOT to specify your search. Using these boolean operators, you can usually get a list of more relevant sites.

Upload While downloading is receiving a file from another computer, uploading is the exact opposite. It is sending a file from your computer to another system. Pretty straight forward. It is possible to upload and download at the same time, but it may cause slower transfer speeds, especially if you have a low bandwidth connection. Because most files are located on Internet servers, people generally do a lot more downloading than uploading.

URL (Uniform Resource Locator) Stands for "Uniform Resource Locator." A URL is the address of a specific Web site or file on the Internet. It cannot have spaces or certain other characters and uses forward slashes to denote different directories. Some examples of URLs are http://www.cnet.com/, http://web.mit.edu/, and ftp://info.apple.com/. As you can see, not all URLs begin with "http". The first part of a URL indicates what kind of resource it is addressing. Here is a list of the different resource prefixes: • • • • • • •

http - a hypertext directory or document (such as a Web page) ftp - a directory of files or an actual file available to download gopher - a gopher document or menu telnet - a Unix-based computer system that you can log into news - a newsgroup WAIS - a database or document on a Wide Area Information Search database file - a file located on your hard drive or some other local drive

The second part of a URL (after the "://") contains the address of the computer being located as well as the path to the file. For example, in "http://www.cnet.com/Content/Reports/index.html," "www.cnet.com" is the address or domain name of the host computer and "/Content/Reports/index.html" is the path to the

file. When a address ends with a slash and not something like ".html" or ".php," the Web server typically defaults to a file in the current directory named "index.html," "index.htm," or "index.php." So, if you type in "http://www.apple.com/" and "http://www.apple.com/index.html," you should get the same page. Go ahead and try it if you have nothing better to do.

Web Page Web pages are what make up the World Wide Web. These documents are written in HTML (hypertext markup language) and are translated by your Web browser. Web pages can either be static or dynamic. Static pages show the same content each time they are viewed. Dynamic pages have content that can change each time they are accessed. These pages are typically written in scripting languages such as PHP, Perl, ASP, or JSP. The scripts in the pages run functions on the server that return things like the date and time, and database information. All the information is returned as HTML code, so when the page gets to your browser, all the browser has to do is translate the HTML. Please note that a Web page is not the same thing as a Web site. A Web site is a collection of pages. A Web page is an individual HTML document. This is a good distinction to know, as most techies have little tolerance for people who mix up the two terms.

Website A website, or Web site, is not the same thing as a Web page. Though the two terms are often used interchangeably, they should not be. So what's the difference? To put it simply, a Web site is a collection of Web pages. For example, Amazon.com is a Web site, but there are millions of Web pages that make up the site. Knowing the difference between these two terms can save you a lot of embarrassment.

Hypertext Hypertext is text that links to other information. By clicking on a link in a hypertext document, a user can quickly jump to different content. Though hypertext is usually associated with Web pages, the technology has been around since the 1960s. Software programs that include dictionaries and

encyclopedias have long used hypertext in their definitions so that readers can quickly find out more about specific words or topics. Apple Computer's HyperCard program also used hypertext, which allowed users to create multi-linked databases. Today, the Web is where hypertext reigns, where nearly every page includes links to other pages and both text and images can be used as links to more content.

Worksheet Activity #3 List other Internet terms. Discuss each.

Chapter 4 Internet basic formats AIFF (Audio Interchange File Format) Stands for "Audio Interchange File Format." AIFF is an audio format originally developed by Apple Computer for storing high-quality sampled audio data. AIFF files are similar to Windows WAVE files in both

size and quality. Both AIFF and WAVE files can hold CD quality audio and therefore can be burned onto an audio CD. Though the AIFF format was created by Apple, audio programs on both the Mac and PC can typically read the files.

Batch File A batch file is a type of script that contains a list of commands. These commands are executed in sequence and can be used to automate processes. For example, some programs may include a batch file that executes a number of commands as the program starts up. A user can also create a custom batch file to automate tedious processes such as copying multiple directories or renaming several files at once. Batch files are run by the COMMAND.COM program, which is part of DOS and Windows. Therefore, batch files can only be run within the Windows operating system. Macintosh and Unix have other scripting tools, such as AppleScript and Unix shell commands, that can be used for similar tasks. Because batch files contain executable commands, it is important not to open unknown batch files on your hard disk or in e-mail attachments. File Extensions: .BAT, .CMD

Bitmap Most images you see on your computer are composed of bitmaps. A bitmap is a map of dots, or bits (hence the name), that looks like a picture as long you are sitting a reasonable distance away from the screen. Common bitmap filetypes include BMP (the raw bitmap format), JPEG, GIF, PICT, PCX, and TIFF. Because bitmap images are made up of a bunch of dots, if you zoom in on a bitmap, it appears to be very blocky. Vector graphics (created in programs such as Freehand, Illustrator, or CorelDraw) can scale larger without getting blocky. File extension: .BMP

DLL (Dynamic Link Library)

Stands for "Dynamic Link Library." A DLL (.dll) file contains a library of functions and other information that can be accessed by a Windows program. When a program is launched, links to the necessary .dll files are created. If a static link is created, the .dll files will be in use as long as the program is active. If a dynamic link is created, the .dll files will only be used when needed. Dynamic links help programs use resources, such as memory and hard drive space, more efficiently. DLL files can also be used by more than one program. In fact, they can even be used by multiple programs at the same time. Some DLLs come with the Windows operating system while others are added when new programs are installed. You typically don't want to open a .dll file directly, since the program that uses it will automatically load it if needed. Though DLL filenames usally end in ".dll," they can also end in .exe, .drv, and .fon, just to make things more confusing. File extension: .DLL

GIF (Graphics Interchange Format) The letters "GIF" actually stand for "Graphics Interchange Format," but you don't need to remember that. What you should know is that a GIF is a compressed image file format. GIF images use a compression formula originally developed by CompuServe (which is why you see the term "CompuServe GIF" in Photoshop, for those of you that care). GIFs are based on indexed colors, which is a palette of at most 256 colors. This helps greatly reduce their file size. These compressed image files can be quickly transmitted over a network or the Internet, which is why you often see them on Web pages. GIF files are great for small icons and animated images, but they lack the color range to be used for high-quality photos. File extension: .GIF

JPEG (Joint Photographic Experts Group)

The term actually stands for "Joint Photographic Experts Group," because that is the name of the committee that developed the format. But you don't have to remember that because even computer nerds will think you're weird if you mention what JPEG stands for. Instead, remember that a JPEG is a compressed image file format. JPEG images are not limited to a certain amount of color, like GIF images are. Therefore, the JPEG format is best for compressing photographic images. So if you see a large, colorful image on the Web, it is most likely a JPEG file. While JPEG images can contain colorful, high-resolution image data, it is a lossy format, which means some quality is lost when the image is compressed. If the image is compressed too much, the graphics become noticeably "blocky" and some of the detail is lost. Like GIFs, JPEGs are crossplatform, meaning the same file will look the same on both a Mac and PC. File extensions: .JPG, .JPEG

MP3 (MPEG-1 Audio Layer-3) Stands for "MPEG-1 Audio Layer-3." It is the most popular compressed audio file format. An MP3 file is about one tenth the size of the original audio file, but the sound is nearly CD-quality. Because of their small size and good fidelity, MP3 files have become a popular way to store music files on both computers and portable devices. There are also many Web sites, like MP3.com and GarageBand.com, that maintain huge archives of audio files in MP3 format. To listen to MP3s on your computer, you'll need an MP3 player like Musicmatch (for Windows) or iTunes (for the Mac). To create an MP3 file from a CD audio track, you'll need an encoder program to convert the audio track to an MP3 file. Once you have converted your favorite songs to MP3 files, you can listen to them on a portable MP3 player, like the Apple iPod or the SonicBlue Rio. File extension: .MP3

MPEG (Moving Picture Experts Group) Stands for "Moving Picture Experts Group." The MPEG organization, which works with the International Organization for Standardization (ISO), develops standards for digital audio and video compression. The group constantly works to develop more efficient ways to digitally compress and store audio and video files. The term MPEG also refers to a type of multimedia file, which is denoted by the file extension ".mpg" or ".mpeg." These files are compressed movies that can contain both audio and video. Though they are compressed, MPEG files maintain most of the original quality of the uncompressed movie. This is why many videos on the Web, such as movie trailers and music videos, are available in the MPEG format. File extensions: .MPG, .MPE, .MPEG

PDF (Portable Document Format) Stands for "Portable Document Format." PDF is a multi-platform file format developed by Adobe Systems. A PDF file captures document text, fonts, images, and even formatting of documents from a variety of applications. You can e-mail a PDF document to your friend and it will look the same way on his screen as it looks on yours, even if he has a Mac and you have a PC. Since PDFs contain color-accurate information, they should also print the same way they look on your screen. To view a PDF file, you need Adobe Reader, a free application program distributed by Adobe Systems. Adobe also makes an Acrobat Plug-in for Web browsers that enables PDF files to be viewed inside a browser window. File extension: .PDF

PNG (Portable Network Graphic)

Stands for "Portable Network Graphic." This format was designed as an alternative to the GIF format (which has been plagued by copyright issues). Like GIFs, PNG files are lossless, meaning they don't lose any detail when they are compressed. They support up to 48-bit color or 16-bit grayscale and typically compress about 5% to 25% better than GIF files. However, they do not support animations like GIFs do. A format similar to PNG, called MNG, is currently under development, and will support animations. File extension: .PNG

PostScript PostScript is a page description language (PDL) that describes a page's text and graphical content. It can be used to define the appearance of graphics and text for both screen and print. The language was developed by Adobe in 1984 and has since gone through may revisions and updates. Before PostScript was introduced, publishing systems relied on proprietary typesetting systems, which often caused incompatibilities between computers and printing systems. In fact, before the days of PostScript, pages that incorporated text, images, and line art had to be manually assembled on a paste-up board and then photographed. The resulting picture was sent to a printing plate, which was used to make copies of the document -- pretty archaic compared to the simple printing options available today. Adobe PostScript makes it possible to produce high quality page content that can include text, images, and line art in a standard format compatible with multiple devices. For example, PostScript (.PS) files will print the exact same way from different PostScript compatible printers. They can also be opened using Adobe Acrobat and will look the same on Macintosh and Windows platforms. In fact, the evolution of PostScript led to the development of Adobe Acrobat, which creates PDF documents. File extensions: .PS, .EPS

Raster Graphic Most images you see on your computer screen are raster graphics. Pictures found on the Web and photos you import from your digital camera are raster graphics. They are made up of grid of pixels, commonly referred to as a bitmap. The larger the image, the more disk space the image file will take up. For example, a 640 x 480 image requires information to be stored for 307,200 pixels, while a 3072 x 2048 image (from a 6.3 Megapixel digital camera) needs to store information for a whopping 6,291,456 pixels. Since raster graphics need to store so much information, large bitmaps require large file sizes. Fortunately, there are several image compression algorithms that have been developed to help reduce these file sizes. JPEG and GIF are the most common compressed image formats on the Web, but several other types of image compression are available. Raster graphics can typically be scaled down with no loss of quality, but enlarging a bitmap image causes it to look blocky and "pixelated." For this reason, vector graphics are often used for certain images, such as company logos, which need to be scaled to different sizes. File extensions: .BMP, .TIF, .GIF, .JPG

RTF (Rich Text Format) Stands for "Rich Text Fomat." This is a file format standardized by Microsoft for creating formatted text files. Unlike a basic text file, an RTF file can include information such as text style, size, and color. The nice thing about the RTF format is that it is a universal format, meaning it can be read by nearly all word processors. File extension: .RTF

TIFF (Tagged Image File Format) Stands for "Tagged Image File Format." It is graphics file format created in the 1980's to be the standard image format across multiple computer platforms. The TIFF format can handle color depths

ranging from 1-bit to 24-bit. Since the original TIFF standard was introduced, people have been making many small improvements to the format, so there are now around 50 variations of the TIFF format. So much for a universal format. Recently, JPEG has become the most popular universal format, because of its small file size and Internet compatibility. File extensions: .TIF, .TIFF

Vector Graphic Unlike JPEGs, GIFs, and BMP images, vector graphics are not made up of a grid of pixels. Instead, vector graphics are comprised of paths, which are defined by a start and end point, along with other points, curves, and angles along the way. A path can be a line, a square, a triangle, or a curvy shape. These paths can be used to create simple drawings or complex diagrams. Paths are even used to define the characters of specific typefaces. Because vector-based images are not made up of a specific number of dots, they can be scaled to a larger size and not lose any image quality. If you blow up a raster graphic, it will look blocky, or "pixelated." When you blow up a vector graphic, the edges of each object within the graphic stay smooth and clean. This makes vector graphics ideal for logos, which can be small enough to appear on a business card, but can also be scaled to fill a billboard. Common types of vector graphics include Adobe Illustrator, Macromedia Freehand, and EPS files. Many Flash animations also use vector graphics, since they scale better and typically take up less space than bitmap images. File extensions: .AI, .EPS, .SVG, .DRW

Zip Windows users will see this term a lot when looking for files on the Internet. A zip file (.zip) is a "zipped" or compressed file. For example, when you download a file, if the filename looks like this: "filename.zip," you are downloading a zipped file. "Zipping" a file involves compressing one or more items into a smaller archive. A zipped file takes up less hard drive space and takes less time to transfer to another computer. This is why most Windows files that you find on the Internet are compressed. To use a zipped file, you'll need to unzip it first. PKZIP for DOS, or WinZip for Windows, are some popular programs that can unzip files for you. Fortunately, these programs can be downloaded for free from Web sites like Download.com. Macintosh files are most often "stuffed" into Stuffit files (.sit), which can be "unstuffed" using Aladdin's Stuffit Expander. The term "Zip" also refers to a product by Iomega. The company makes a removable storage device called a Zip Drive. Depending on the model, these drives can hold 100, 250 or 750 MB Zip disks. They are usually used for backup and for transferring large files to different locations. However, Zip drives are not as fast as hard drives, so it is usually not a good idea to run programs off them. File extension: .ZIP

Worksheet Activity #4

Research data’s that discuss how these file formats work.