1、 Introduction to computer 1 .Computer Literacy The vocabulary of computing is all around you. Before the advent of computers, memory was the mental ability to recall previous experiences； storage was an area where you kept out -of-season clothing； and communication was the act of exchanging opinions
2、 and information through writing, speaking, or signs. In todays world, these words and countless others have taken on new meanings as part of the common terminology used to describe computers and their uses. When you hear the word computer, initially you may think of those found in the workplace the
3、 computers used to create business letters, memos, and other correspondence； calculate payroll； track inventory； or generate invoices. In the course of a day or a week, however, you encounter many other computers. Your home, for instance, may contain a myriad of electronic devices, such as cordless
4、telephones, VCRs, handheld video games cameras, and stereo systems, which include small computers. Computers help you with your banking in the form of automatic teller machines (ATMs) used to deposit or withdraw funds. When you buy groceries, a computer tracks your purchases and calculates the amoun
5、t of money you owe； and sometimes generates coupons customized to your buying patterns. Even your car is equipped with computers that operate the electrical system, control the temperature, and run sophisticated antitheft devices. Computers are valuable tools. As technology advances and computers ex
6、tend into every facet of daily living, it is essential you gain some level of computer literacy. To be successful in todaywo4ld, you must have knowledge and understanding of computers and their uses. 2. What is a computer and what does it do A computer is an electronic machine, operating under the c
7、ontrol of instructions stored in its own memory, which can accept data (input), manipulate the data according to specified rules (process), produce results (output), and store the results for future use. Data is a collection of un-organized facts, which can include words, numbers, images, and sounds
8、. Computers manipulate and process data to create information. Information is data that is organized, has meaning, and is useful. Examples are reports, newsletters, a receipt, a picture, an invoice, or a check. Data is processed and manipulated to create a check. Data entered into a computer is call
9、ed input. The processed results are called output. Thus, a computer processes input to create output. A computer also can hold data and information for future use in an area called storage. This cycle of input, process, output, and storage is called the information processing cycle. A person that co
10、mmunicates with a computer with a computer or uses the information it generates is called a user. The electric, electronic, and mechanical equipment that makes up a computer is called hardware. Software is the series of instruction that tells the hardware how to perform tasks. Without software, hard
11、ware is useless； hardware needs the instructions provided by software to process data into information. 3.The components of a computer A computer consists of a variety of hardware components that work together with software to perform calculations, organize data, and communicate with other computer.
12、 These hardware components include input devices, output devices, a system unit, storage devices, and communications devices. 3.1 Input Devices An input device allows a user to enter data and commands into the memory of a computer. Four commonly used input devices are the keyboard, the mouse, a micr
13、ophone, and a PC camera. A computer keyboard contains keys that allow you to type letters of the alphabet, number, spaces, punctuation marks, and other symbols. A computer keyboard also contains special keys that allow you to allows you to move the pointer. You also can make choices and initiate pro
14、cessing on the computer by using a mouse. A microphone allows you to speak to the computer in order to enter data and control the actions of the computer. A PC camera allows others to see you wh ile communicating with you, as well as allowing you to edit videos, create a movie, and take digital photographs. 3.2 Output Devices A printer produces text and graphics, such as photographs, on paper or other hardcopy medium. A monitor, which looks like a television screen, is used to
