Webopedia
Whatis.com
VDT: Video Display Terminal or sometimes Visual Display Terminal
VDU: Visual Display Unit
RSI: Repetitive Strain Injury
VLF: Very Low Frequency
ELF: Extremely Low Frequency.
Ergonomics: The design of safe and capable machiens for humans, i.e, furniture that prevents backaches and muscle cramps. In computers, safe and comfortable keyboards and monitors are created.
Storage Devices
Tape Cartriges: Units like audio tapes holding 0.25 inch tapes mostley used to backup hard disks and can store up to about 10Gb's of data.
Hard Disks: Internal Unit used on PC systems. can store up to about 100Gb's of Data and may hold data such as the Operating system (e.g., Windows) applications software (e.g. word processors) and utilities (e.g. file managers)
Floppy Disks: slower than a Hard Disk as it spinns slower, it can hold 1.4Mb's of data. mainly used to transfer data (usually documents) from one computer to another without a network. it can also be used to backup personal computer systems.
Zip Disks: As the regular Floppy disk has a small capcity of 1.4Mb's, the zip drive was created to hold 100 or 250Mb's of data for a larger capacity.
Optical Disk: Often Called CD-ROM (Compact Disk - Read Only Memory), this is the same size as an audio CD and is read the same way. Data cannot be changed or deleted as it is Read Only Memory. Access is slower than a Hard disk as it's spin is slower. It can store about 650Mb's of data. This is used when data doen not need to be changed frequently and can be used to transfer data from one computer to another when no network is found. they are cost efective as software that would normally take up about ten floppy disks only take up one CD-ROM.
CD-R's or WORM (Write Once Read Many) are writable compact disk's but unlike floppy disks, can only be written on once and not deleted or altered. They are then CD-ROM's.
CD-RW's are re-writable CD's on which you can use it pretty much like a floppy disk except that it has a larger capacity and is therfore more useful in transferring large amounts of data from one compute to another. This has a limited lifetime though.