Computers: Tools for an Information Age
Chapter 1
Objectives Describe the three fundamental characteristics of
computers Describe at least four areas of society in which computers are used Identify the basic components of a computer system: input, processing, output, and storage List some common input, output, and storage media Distinguish data from information Describe the significance of networking Explain the significance of the Internet Explain the various classifications of computers
Contents Information Age Computer Literacy Where Computers Are Used Computer System Network Classifications of Computers
Information Age Evolving more rapidly than
Industrial Age Will continue into the current century Greater impact will be felt among network communities
Forging a Computer-Based Society: From physical to mental From muscle-power to brain-power
What is a computer? A computer is a special type of electronic calculating device with internal storage (RAM- hardware) capabilities that performs mathematical and logical operations (ALU) on the data through its Central Processing Unit-CPU, (hardware) based on the set of program instructions or language (software) and produces result in the form of meaningful and useful output.
Computer A machine that can be
programmed to accept data (input), process it into useful information (output), and store it away (in secondary storage device) for safekeeping or later reuse Process is directed by the software but is performed by the hardware.
CAPABILITIES OF COMPUTER 1. High-speed processing - the computer can process data faster than any other machine with its speed of 1/1M of a sec 2. Repetitiveness - a computer can perform the same operation millions of times in exactly the same way. 3. Accuracy - a computer's high-speed processing gives 99.99% error free results. 4. Arithmetic and Logical Operations - the computer can make decisions based on alternative course of action. 5. Store and Retrieve Information - computers can store information in the memory and use them when needed.
Limitations of Computer 1. A computer cannot generate information on its own. It must be told what to do, when to start, stop, compute, and make the next move via a program 2. A computer can detect errors but generally cannot correct them on its own. 3. Computers cannot combine ideas or take the best parts or several ideas to come up with a brand new idea of its own. 4. Computers need periodic maintenance support. 5. A Computer is subject to occasional breakdown and wear out .
A Computer Now… Where is it used? Bank withdrawal Supermarket and department stores Drive the car E-Commerce Do you need a Personal Computer? Many Filipinos have one at home Many more use at work Will I use a computer in my future career? Almost every job will involve use of a computer
Computer Literacy Awareness
Importance Versatility Pervasiveness in our society
Knowledge
What are computers How do computers work Terminology
Interaction
Use some simple computer applications
Where Computers Are Used Education Teaching and testing
aid
Learning by doing Computer-based
instruction
E-Learning and
Distance Learning
Computers in Retailing Bar codes for pricing and
inventory Recording and monitoring in
Shipping
Computers in Energy Locate oil, coal,
natural gas, and uranium Monitor the power network Meter reading or ground works monitoring
Computers for Law Enforcement National fingerprint files National files on criminal Computer modeling of
DNA – Deoxyribonucleic Acid
Computers in Transportation Cars- automatic Run rapid transit systems- LRT, MRT Load containerships Track railroad cars Monitor airline traffic
Computers in Finance Record keeping to monitor expense Banking by phone or on-line request Credit cards
Computers in Agriculture Crop growth information
Feed combinations
Mixed breeding of plants
Livestock breeding and
performance
Computers in Government Forecast weather Manage parks Process immigrants Social Security benefits Taxes Municipal and City Government Services
Computers at Home Educational tool Record keeping Letter writing Budgeting Drawing and editing pictures Newsletters Connecting with others Digital Entertainment
Computers in Health and Medicine Monitor patients Electronic imaging Diagnose illnesses Assist the disabled
Computers for Robotics Perform jobs that are dangerous for humans Factory work Mimic how human works
Where Computers Are Used The Sciences Research Simulation
Connectivity Communication Telecommuting
Where Computers Are Used Training Airline pilots Railroad engineers
Paperwork • Term paper • Record keeping
Computers are all around! Grocery store School Library Bank Mail
We interact with computers everyday!
Computer System Components People Software Hardware Dataware
People Computer programmer – person who
writes programs Users or End-users – make use of the
computer’s capabilities
Software Programs- such as Windows
Operating System, MS-Office Set of instructions that directs the
hardware to do a required task and produce the desired results
Hardware Basic Components of a Computer
Function of Computer System Data handling I P O S
Input Process Output Storage
Input devices Accept data or commands and convert them to
electronic form
Getting data into the computer
Typing on a keyboard
Pointing with a mouse
Scanning with a wand reader or bar-code reader
Terminal
Output devices • Convert from electronic form to some other form • May display the processed results • Usable information Monitor or screen
Printer
Text Numbers
Black and white Color
Symbols Art Photographs Video
The Processor Central Processing Unit (CPU) Converts data to useful information Interpret and execute instructions Communicate with input, output and
storage
Two Types of Storage Secondary storage
long-term storage Primary storage or memory
temporary storage
Memory / Primary Storage RAM - Temporary storage Holds input to be processed Holds results of processing Contains the programs to control the
computer and manipulate input into output
Volatile
Secondary Storage Long-term storage Non-volatile For safekeeping and later re-use
Secondary Storage Examples Magnetic disks – read and written by magnetic disk
drive Hard disk Diskette
Optical disks – read and written by optical disk drives
CD-ROM DVD-ROM
Magnetic tape – read and written by magnetic tape
drives Primarily used for back-up
Computer System Computer
CPU Memory
Peripheral equipment
Connected to the computer by a cable Input, output, storage
Network Definition A system that uses communications equipment to connect computers and their resources. Types Local area network (LAN) – connects computers in close proximity, within a building or a particular location
Metropolitan area network (MAN) – connect computers between buildings in the same geographic area
Wide area network (WAN) – connects computers over great distances
Internet
Collection of networks No ownership No central source for services available No comprehensive index of what information is available
Connects Everyone! Individuals Businesses Organizations
Libraries Research labs Government
Getting Connected User’s computer must connect to a server Server must communicate using TCP/IP The user can purchase access to a server
from an ISP (Internet Service Provider)
Internet – What Can You Do? WWW – World Wide Web FTP – File Transfer Protocol E-mail UseNet IRC – Internet Relay Chat Bulletin Boards
World Wide Web • Browser – program that allows the user to move around and explore the Internet • Use the mouse to point and click on text and graphics • Web page • Web site • Home page
Classifications of Computers According to purpose According to data handled According to size
According to purpose General purpose- a machine that can be
used to process many types of applications. Ex microcomputers Special purpose- a machine that can be used for a specific application or just ONE application. Ex: Weather Forecasting and Airlines Reservation
According to data handled Analog computers- a computer that
manipulates continuous or approximate types of data Digital computers - a computer that manipulates discrete types of data Hybrid computers- a computer that can manipulate both analog or digital types of data
According to size or capacity Microcomputer – smallest in size and the cheapest.
It can handle thousands of records. Minicomputer – the medium size computer, bigger and more expensive than the microcomputer Mainframe – a large computer that can handle millions of data, Support multiple user, does server tasks Supercomputer – is a very large computer that
manipulates billions of data
Classifications of Computers Use the computer that fits your needs Based upon
Size Speed Cost Portability Number of simultaneous users supported Available software Typical use
Personal Computers Other names PC Microcomputer Home computer Categories Low-end functional Fully powered Workstations Net computer or net box (Web TV) Desktop Models
Notebook Computers Portable Lightweight Fits in a briefcase Battery operated Laptop Larger Heavier More expensive that
desktop models
Handheld Computers Personal Digital Assistant (PDA) Scheduling Addresses Handwritten input May offer wireless e-mail and fax Pocket More power than PDA Runs basic productivity software