"Computer Applications Introduction to Computers"
Computer Applications Introduction to Computers By: Richard W. Lipham - Waltrip High School The Operating System an executive program that controls execution of all other programs and operations of all system components such as the disk drive, and printer. Operating System Platforms PC Apple Macintosh Operating Systems Macintosh PC Mac OS 9 Windows XP Mac OS 8 Windows 2000 ME Mac OS 7.5 Windows 98 Mac OS 7.1 Windows 95 Windows NT Windows 3.x DOS Linux Unix Internal Components of the Computer CPU - Central Processing unit Mother Board Memory Chips Power Supply Hard Drive Disk Drive CD/DVD Drive Battery CPU - Central Processing unit the system component that contains within "memory" the executing program and, following instructions, causes arithmetic, logical, and input/output operations to be performed; also called "processor". The Processor uses digital data known as binary numbers Bit - a single binary number. It is either a 1 or a 0. Byte - 8 bits. Kilobyte - 1024 bytes. Megabyte - 1,000 kilobytes Gigabyte - 1,000 megabytes The Binary System The binary system based on powers of 2. In the binary system, only the digits 0 and 1 are used. Thus, the first ten numbers in binary notation, corresponding to the numbers: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 0, 1, 10, 11, 100, 101, 110, 111, 1000, 1001 Megahertz/Gigahertz is the speed at which the processor operates. Hertz is a unit of frequency, equal to 1 cycle per second. The term is combined with metric prefixes to denote multiple units such as the kilohertz (1,000 Hz), megahertz (1,000,000 Hz), and gigahertz (1,000,000,000 Hz). Mother Board a rigid, slotted board upon which other boards that contain the basic circuitry of a computer or of a computer component can be mounted. Memory Chips- RAM Random Access Memory. Ram is the section of memory that is accessible to the computer user, used to run applications etc. RAM allocation 64 Megabytes of ram Available memory to run programs The system uses this much. RAM allocation 64 Megabytes of RAM Available memory to 20.3 run other programs An open application 15.9 uses RAM 27.8 The system uses this much. Memory Chips- ROM Read Only Memory These chips have etched in them the instructions that tell the computer how to run. ROM is the section of memory reserved for system use only. Power Supply a device that provides power to electronic equipment, computers, etc. Hard Drive A hard drive is a high- capacity storage device with much faster access time than a flexible diskette. Disk Drive An electromechanical device for recording and retrieving data from a diskette; an input/output device. 3 1/2” floppy disk (1.44 Meg) ZIP disk (100 Meg/250) CD/DVD Drive A compact disk containing information or interactive applications that can be accessed by the computer. Battery Maintains in the memory the preferences needed by the computer; control panel settings, time, etc. External Components for the Computer Monitor Keyboard Mouse/Trackball/Touch pad Speakers Monitor a component, CRT, connected to a computer, used for viewing data. Keyboard The operator’s communication link back to the computer; an input device Mouse/Trackball/Touch Pad a palm-sized, button- operated device that can be slid over a desktop, moving a wheel or ball, used to move the cursor on a CRT to any position. Speakers an electroacoustic device, often housed in a cabinet, that is connected as a component in a computer system, its function being to make speech or music audible. The History of Computers http://library.thinkquest.org/22522/index.html