1. Unit 1 — Computer Basics
Lesson 1 — Understanding Computers and Computer Literacy

2. Lesson 1 – Understanding Computers and Computer Literacy
Objectives
Define the term computer.
Describe a computer system.
Explain the importance of computer literacy.
Discuss the history of computers.
Identify how computers and technology are used in our daily lives.
Lesson 1 – Understanding Computers and Computer Literacy

3. Objectives (continued)
List the categories of computers and their uses.
Describe communications.
Define networks, intranets, and extranets.
Discuss the use of the Internet and the World Wide Web.
Lesson 1 – Understanding Computers and Computer Literacy

4. Lesson 1 – Understanding Computers and Computer Literacy
What Is a Computer?
A computer is an electronic device that
Receives data.
Processes the data it receives.
Stores the data in memory or on some storage device such as a disk or CD.
Outputs information on a device such as a monitor or printer.
Lesson 1 – Understanding Computers and Computer Literacy

5. The Processing Cycle of a Computer
This figure shows the typical processing cycle of a computer. Once it receives a set of data, the computer processes it and produces a result at the end of the cycle.
Lesson 1 – Understanding Computers and Computer Literacy

6. Lesson 1 – Understanding Computers and Computer Literacy
What Does a Computer Do?
As complex as some computers may be, they all essentially perform only two operations:
Arithmetic operations, such as addition, subtraction, and so on.
Logical operations, such as comparing two values and taking some action based on the result of the comparison.
Lesson 1 – Understanding Computers and Computer Literacy

7. What Makes a Computer So Powerful?
Although computers only perform the basic operations discussed on the last slide, they
Perform those functions very quickly.
Produce accurate and reliable results.
Store large amounts of data.
Provide versatility through various applications.
Share resources with other computers.
Are becoming more powerful and easier to use.
Lesson 1 – Understanding Computers and Computer Literacy

8. Lesson 1 – Understanding Computers and Computer Literacy
How Are Computers Used?
Computers have changed everyone’s lives and are used every day for
Education: Online instruction and degree programs.
At Home: Appliances and home security systems.
Business: Computers are used to track inventory, print invoices, track payments, and do just about anything a business needs to do.
Lesson 1 – Understanding Computers and Computer Literacy

9. Categories of Computers
There are several types of computers suited for a variety of uses, including
Desktop computers: All components fit on or under a desk.
Notebook: Smaller and more portable than a desktop; commonly called a laptop.
Handheld or palmtop: Used primarily for calendars and address books.
Mid-range server: Used by medium-sized companies and generally supports hundreds of users.
Mainframes: Large, very expensive machines that can support thousands of users; used by large corporations.
Supercomputers: Used for specialized operations requiring mathematical operations.
Lesson 1 – Understanding Computers and Computer Literacy

10. Types of Personal Computers
Desktop Computer Notebook Handheld
Lesson 1 – Understanding Computers and Computer Literacy

11. What Is Electronic Communication?
Electronic communication is the technology that allows computers to talk to each other and other devices.
It has made the Internet, , online shopping, and other processes possible.
There are four components of electronic communication:
Sender: The computer sending a message.
Receiver: The computer receiving the message.
Channel: The media that carries the message.
Protocol: The rules that govern the processing of a message between computers.
Lesson 1 – Understanding Computers and Computer Literacy

12. Electronic Communication Components
Computer A sends a message to Computer B.
The message travels via the channel, following the rules defined by the protocol being used so that each computer can understand the message.
Lesson 1 – Understanding Computers and Computer Literacy

13. Lesson 1 – Understanding Computers and Computer Literacy
Network Systems
A network consists of multiple computers connected to each other to share data and resources.
Data and software programs are usually stored on a central computer called a server.
When the network computers are located in the same general area, such as the same building or a department, it is called a local area network.
Lesson 1 – Understanding Computers and Computer Literacy

14. A Typical Network Layout
In a typical network layout, the client or user computers are connected to a hub, which is also connected to the server.
Hub
Data and programs are stored on the server. All clients can access data and pro-grams through the server and can access the printer attached to the server.
Client or user computers
Lesson 1 – Understanding Computers and Computer Literacy

15. Lesson 1 – Understanding Computers and Computer Literacy
The Internet
The Internet evolved from a government research project that enabled the military and scientists around the world to share information.
Today it is the largest network in the world.
It is used daily by millions of computer users.
It has become a critical and valuable business tool used by businesses of all sizes.
Lesson 1 – Understanding Computers and Computer Literacy

16. Other Types of Networks
In addition to the networks already discussed, there are also some other types in common use today:
Wide area network: This is a local area network spread over a wider region such as a city, state, or country.
Intranet: This is a network set up for employees of a business or students at a university that is not accessible to users outside of those institutions.
Extranet: This is typically an intranet that allows certain users, such as suppliers or customers, to access the internal network.
Lesson 1 – Understanding Computers and Computer Literacy

17. Lesson 1 – Understanding Computers and Computer Literacy
Summary
A computer is an electronic device that receives data, processes data, and stores data to produce a result.
The first computers were used by the military and government installations.
The first personal computer was sold in 1977.
Computers can be found in almost every aspect of our lives.
Lesson 1 – Understanding Computers and Computer Literacy

18. Lesson 1 – Understanding Computers and Computer Literacy
Summary (continued)
There are different types of computers including microcomputers, notebook computers, personal digital assistants, minicomputers, mainframe computers, and supercomputers.
Computers are classified by size, speed, and application.
Lesson 1 – Understanding Computers and Computer Literacy

19. Lesson 1 – Understanding Computers and Computer Literacy
Summary (continued)
A computer system consists of the following components:
Hardware: Tangible physical equipment.
Software: The intangible set of instructions that tells the computer what to do. This set of instructions is called a software program.
Data: The information entered into a computer to be processed.
People: The users who enter the data and use the output.
Lesson 1 – Understanding Computers and Computer Literacy

20. Lesson 1 – Understanding Computers and Computer Literacy
Summary (continued)
Electronic communication is the transmission of text, numeric, voice, or video data from one machine to another. The four components of electronic communication are as follows:
Sender: The computer that is sending the message.
Receiver: The computer receiving the message.
Channel: The media that carries or transports the message. This could be telephone wire, coaxial cable, microwave signal, or fiber optic.
Protocol: The rules that govern the orderly transfer of the data sent.
Lesson 1 – Understanding Computers and Computer Literacy

21. Lesson 1 – Understanding Computers and Computer Literacy
Summary (continued)
A local area network connects multiple computers within a building. It allows the sharing of data and resources.
The Internet was originally developed so information could be shared by government researchers around the world.
In the future, computers will be more powerful and less expensive.
Lesson 1 – Understanding Computers and Computer Literacy