Week 4 Introduction to computers : reviews

1. Week 4 Introduction to computers : reviews

2. A World of Computers • Computers are everywhere. • Through computers, society has instant access to information from around the globe. • People also spend hours of leisure time using a computer.

3. What Is a Computer? • An electronic device, • Operating under the control of instructions stored in its own memory • Accept data, • process the data according to specified rules, • Produce results, • And store the results for future use

4. Data and Information • Data is a collection of unprocessed items, which can include text, numbers, images, audio, and video. • Information conveys meaning and is useful to people.

5. Data and Information

6. The Components of a Computer • Input Devices • hardware component that allows you to enter data and instructions into a computer • Output Devices • hardware component that conveys information to one or more people. • Storage Devices • Storage holds data, instructions, and information for future use.

7. The Components of a Computer • System Unit • CPU (central processing unit) • electronic component that interprets and carries out the basic instructions that operate the computer • Memory • electronic components that store instructions waiting to be executed and data needed by those instructions.

8. The Components of a Computer • Communications Devices • hardware component that enables a computer to send (transmit) • and receive data, instructions, and information to and from one or more computers or mobile devices.

9. Advantages of Using Computers • Speed: • Many computers process billions or trillions of operations in a single second • Reliability: • because they rarely break or fail • Consistency: • a computer will produce the same results

10. Advantages of Using Computers • Storage: • Computers store enormous amounts of data and make this data available for processing anytime it is needed • Communications: • today can communicate with other computers, often wirelessly

11. Disadvantages of Using Computers • Violation of Privacy • individuals have found their privacy violated and identities stolen. • Public Safety • Some of these unsuspecting, innocent computer users have fallen victim to crimes committed by dangerous strangers • Impact on Labor Force • the skills of millions of employees have been replaced by computers

12. Disadvantages of Using Computers • Health Risks • Prolonged or improper computer use can lead to health injuries or disorders • Impact on Environment • Computer manufacturing processes and computer waste are depleting natural resources and polluting the environment

13. Networks and the Internet • A network is a collection of computers and devices connected together • The Internet is a worldwide collection of networks that connects millions of businesses, government agencies, educational institutions, and individuals

14. World Wide Web • The Web, one of the more popular services on the Internet • The Web contains billions of documents called Web pages. • A Web page can contain text, graphics, animation, audio, and video. • A Web site is a collection of related Web pages.