Section 1

7th Grade Keyboarding

(p. 4) Types of Computers

A computer is an electronic device that accepts input, processes data, stores data and produces output.

Data are the words, figures, sounds and graphics that describe people, events, things and ideas to produce output.

Supercomputer most powerful, largest and fastest Ex – predict hurricanes

Mainframes Used by business and government to process large amount of

information Ex – payroll checks for thousands or maintain records for millions of

citizens

Types of Computers

Personal ComputersDesktop computer-designed to sit on a deskLaptop computer-portableSmaller, less powerful

Handheld Computers (PDA’s)Fit in palm of handMost have fewer capabilities

Personal Computer Hardware

Computer Case-CPU, “brains” Monitor-screen Keyboard Mouse Memory-storing, “remembering” instructions Disk Drive – reading/storing information Speakers

Input, Output, and Storage Devices

(p. 6) Computer Input Devices

Hardware that allows you to communicate with your computer. Keyboard/Ergonomic keyboard Mouse/Wireless mouse Trackball-similar to mouse, ball on topside Track Point-device used to move pointer by pushing up, left,

right or down Touchpad – drag finger over to control pointer Touch screen – use fingers to make selections Scanner Microphone Bar Code reader/scanner

(p. 8) Computer Output Devices

Monitor-size measured diagonally from one corner to the other CRT Flat panel/LCD

Printer Dot matrix-ribbon striking pins Inkjet-spray ink unto paper, output similar to laser,

cheaper than laser Laser-fastest, most expensive, uses powdery

substance called toner Speaker

(p. 14) Magnetic Storage Devices

Use oxide coated plastic storage media called mylar Floppy disk, hard disk, tape drives

Floppy disks (3 ½” diskettes) – flat circles of iron-coated plastic enclosed in a hard plastic case

Hard disk drive – contains several iron-oxide covered metal platters sealed in a case inside the computer.

Tape drive– resemble video or audio tapes – used to back up large quantities of stored information, very slow.

(p. 16) Optical and Flash Storage

Optical storage devices use laser technology to read and write data on silver platters. Examples – CD’s, DVD’s CD’s – first optical storage device, up to 700 MB DVD’s – store up to 9.4G of data depending upon

whether data is stored on both sides and how many layers on data each side contains

Flash Drives – plug directly into USB drive, portable, large storage capacity 32MB to 6 GB