Computer Introduction PDF

1 2 3 4 5 6  Computers need a language they understand. Binary language, consists of two digits: 0 and 1. Each 0 and 1 is a binary digit, or bit for short. Eight binary digits (or bits) combine to create one byte. In computers, each letter, number, and special character consists of a...

1 2 3 4 5 6  Computers need a language they understand. Binary language, consists of two digits: 0 and 1. Each 0 and 1 is a binary digit, or bit for short. Eight binary digits (or bits) combine to create one byte. In computers, each letter, number, and special character consists of a unique combination of eight bits. Files can be quite large, containing thousands or millions of bytes. 7 8  An input device enables you to enter data and instructions into your computer. A keyboard is used to enter typed data and commands, and a mouse is used to enter user responses and commands. Microphones input sounds, and scanners and digital cameras input nondigital text and digital images, respectively. 9  An output device lets you send processed data out of your computer in the form of text, pictures, sounds, or video. The most common output device is a monitor, which displays text, graphics, and video as soft copies (copies you can see only on-screen). Another common output device is a printer, which creates hard copies (copies you can touch) of text and graphics. Speakers and earphones (or earbuds) are the output devices for sound. 10  An output device lets you send processed data out of your computer in the form of text, pictures, sounds, or video. The most common output device is a monitor, which displays text, graphics, and video as soft copies (copies you can see only on-screen). Another common output device is a printer, which creates hard copies (copies you can touch) of text and graphics. Speakers and earphones (or earbuds) are the output devices for sound. 11 A Hertz is a single oscillation (up-and-down movement) per second of an electromagnetic wave. When coupled with the prefix mega, it refers to millions of wave oscillations per second; when used with the prefix giga, it refers to billions of wave oscillations per second. 400 MHz chip has a clock that receives electricity and switches on and off 400 million times per second. It is twice as fast as a chip that has a 200 MHz clock. Similarly, a 1.2 GHz chip is three times as fast as a chip with a 400 MHz clock. A personal computer’s overall speed and efficiency, however, depend not only on the speed of the CPU but also on the following: Size of RAM. Speed and capacity of the hard disk Speed of the bus. If the CPU operates at 1.6 GHz and the bus at 50 MHz, the bus slows the computer down when the CPU is communicating with cards in the bus slots. More recent bus speeds, however, reach 1,333 MHz and more. 12  A mainframe supports many users and programs simultaneously. A supercomputer performs complex calculations rapidly. Supercomputers are designed to execute a few programs as quickly as possible. An embedded computer is a specially designed computer chip that resides in another device, is self-contained, and has its own programming. A personal computer is a general-purpose, cost-effective computer that is designed to be used by a single end-user. A smartphone offers a wide assortment of apps, media players, high-quality cameras, and web connectivity. 13 14 15 16 17 See example program pr1-01.cpp 18