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What makes a Computer a Computer?  Receives data  Processes data  Stores data  Produces a result 2

Types of Computers 3  What are their functions?  Mainframe – very large and expensive capable of supporting hundreds of users simultaneously.users  Server - high performance computers used to provide services to many end users or clients.  Workstation – high-powered business computers designed for high-end applications like CAD.

Parts of a Computer 4

Measurements  Hertz – measures processor speed in cycles per second.  500 MHz = 5 million cycles per second.  Pixels – measures monitor resolution.  A pixel is a single point in a graphic image.  Monitors are divided into millions of pixels, arranged in rows and columns.  The pixels are so close together that they appear connected.  Bps – measures data transmission speed in bits per second.  Kbps, Mbps, Gbps… 5

Input/Output  Input Devices – a device that feeds data INTO a computer.  Keyboard, mouse, scanner, microphone…  Output Devices – anything that comes OUT of a computer.  Monitor, printer, speakers… 6

Hardware/Software  Hardware – objects that you can actually touch  disks, disk drives, display screens, keyboards, printers, boards, and chips.  Software – untouchable, it exists as ideas, concepts, and symbols, but it has no substance.  Applications Software, Operating Systems  Microsoft Word, AutoCAD, QuickBooks… 7

Ports 8

Saving Data  To copy data from a temporary area to a more permanent storage medium.  Any changes made to a file are stored in a buffer  The buffer is temporary -- as soon as you exit the program or turn off the computer, the buffer disappears.  To record your modifications to the file on the disk, you must save the file. When you do this, the file copies the contents of the buffer back to the file on the disk, replacing the previous version of the file. 9

Methods of Saving  C: Drive – saves to your hard disk on your local computer ONLY.  H: Drive – saves to your Home Directory on the school server. Files are accessible from any computer in the school.  D: Drive – Saves to a cd or dvd.  F: Drive – Saves to temporary storage (flashdrive)  A: Drive – Saves to a floppy disk. 10

Types of Memory  RAM – Random Access Memory  Memory available to programs  Erased when computer is powered off  ROM – Read Only Memory  Used to store programs that boot the computer and perform diagnostics. 11

Operating System  Operating systems perform basic tasks:  recognizing input from the keyboard  sending output to the display screen  keeping track of files and directories on the disk  controlling peripheral devices such as disk drives and printers.  Ex: Vista, Windows XP 12

Terms  Peripherals – a computer device that is not part of the central computer.  Plug and Play – the operating system recognizes the new device when it is plugged in and takes care of all the configuring tasks.  Troubleshooting – analyzing problems to correct faults in the system.  Utilities – programs used to complete specialized tasks related to managing the computers resources. Ex: Antivirus programs 13

Resources 