glossary of computer terms (part 1)
- what do those computer words mean,
- and what do all the bits and pieces do?
what's in front of you
computer
- literally "with reckoning": a counting machine
- a calculator, the chip inside your microwave, an abacus or your own mind
- anything that can count is a computer
what's in front of you
monitor
- literally "to advise": something that advises you what is happening
- the monitor is similar to a TV, but has electronic parts which match with your computer's information, so it can display (show) what you and the computer are doing together
what's in front of you
keyboard
- the keyboard is an input device, a way for you to put information into your computer
- apart from the normal typing keys, the computer keyboard has special keys which can all make using a computer easier
- it is definitely worth reading your operating system manual, and the manual of any program you use, to learn the 'keyboard shortcuts' and 'function keys' which can save you time
what's in front of you
mouse
- a more recent input device, which cuts down on typing, allows you to communicate with your computer by "pointing and clicking"
- on a laptop the mouse job is done by a 'trackball' or 'trackpad', but the principle is the same
- learning to move the pointer on the screen by positioning your hand or fingers, then 'clicking' the right way, saves you a lot of time
- a mouse mat helps grip the moving trackball under the mouse, and protects it (hopefully) from getting grit and gunk rolled inside
- your manual will give instructions on how to clean your mouse when it gets 'sticky' or won't move well
other input devices include:
'touch screens' (where you touch areas on the screen directly) and
voice-controlled computers (where you speak the commands);
all still very expensive
what's in front of you
floppy disk drive
- this drive reads (to the computer)the information on floppy disks, and also writes (from the computer) information onto floppy disks
- still the quickest way to move documents and other small files around
- also used to backup (keep a spare copy of) your own files
what's in front of you
floppy disk
- older floppy disks (five-and-a-quarters) were easily damaged, and measured 5.25 inches across the middle ('in diameter')
- a current floppy disk (three-and-a-half) has a harder plastic casing, and measures 3.5" in diameter
- inside all 'floppies' is a round shape (disk) of 'film', very delicate and definitely floppy!
- the metal slider (on the end you push into the drive) protects the floppy bit of film while it is outside the drive;
it slides aside when the disk is inside the drive, so the drive 'heads' can read it;
similar to the way videocassette film is protected by a hinged, rigid cover which clicks back when the cassette is being read in the video player, but stays in place over the video film whenever the cassette is not inside the player
- 3.5" floppies come in DD ('double density', holding 750k of information) and HD ('high density', holding 1.4 Mb of information)
- floppies are convenient but still very fragile: they need to be replaced regularly, and kept away from anything magnetic
- floppies' greatest advantage (their portability) is their greatest risk: they go from person to person and from computer to computer: they need to be virus-scanned whenever this happens
what's in front of you
CD-ROM drive
- this drive uses a laser to read (read-only) the information in the tiny but complex pattern stamped permanently onto computer compact disks
- drives are marketed in 'speeds' from 1X to 24X (the current standard)
- more complex CDs require faster CD drives
- faster CD drives require faster computer processors
what's in front of you
CD-ROM
- means Compact Disk - Read Only Memory
- CD's are much tougher than floppies, and hold more than 600Mb of information
- CD-writer drives are now available, though expensive, so people can burn their own CDs, e.g. to backup files permanently
- established computer shops or print shops now have their own CD-writers, and will backup your files by burning them onto CD for you, for a fee
- "Image Magic" photo shops will do the same thing with your photos, with an initial cost to start one CD, then burning each new lot of photos onto that CD as you go, until the CD is full
changes in CD-ROM technology
Current CD-ROM writers and readers use a 'red laser' beam to burn in and then read an incredibly tiny pattern of ridges on the disk.
A 'blue laser' beam is even narrower, and 'blue laser' drives have been possible for quite a while.
When they come out, this will mean that this even narrower beam of light will burn even tinier ridges on the CD, and thus will be able to make a lot more ridges in the same space, store (and be able to read) a lot more information on the same CD.
what's in front of you
printer
- dot-matrix printer, the most widespread printing option for ages, available in both B&W and colour, very cheap now but less popular because of low resolution
(a lot of space between dots on the page, so the words or picture don't look 'whole', literally the information is not all together in one place)
- uses a B&W or colour ribbon a bit like a typewriter ribbon
- inkjet printer, the current printing option in both B&W and colour,
due to falling prices and increasing resolution
(now up to 1440x1440 dpi, dots per square inch across and down),
advertised to give 'photo-quality' printing on special paper
- uses B&W and colour ink cartridges
- laser printer, very high quality, B&W now becoming affordable but colour still very expensive
if you want top-quality printing, an established computer or print shop will be able to offer you laser printing, in colour and some even in larger sizes (e.g. A3)
- uses B&W and colour toner cartridges a bit like photocopiers'
what's in front of you
speakers
- multimedia was an advertising tag for computers which meant that your computer would offer quality images (including video), and sound at hi-fi (high-fidelity, very true to the original) levels and in stereo
- 'multimedia' literally means many (multi) ways to get through (media)
- speakers anywhere near computers must be 'shielded' inside to protect them from some pretty awful feedback noise
- more recent computer speakers do produce good quality sound, when matched with the right hardware (in this case circuits inside the computer) to produce better sound,
- if that's not what you're getting, you need to
- try different sound files (e.g. an audio CD in your CD-drive) to see if you've just got low-quality sound files, quite common in computer games (blink, bing, boinngg)
- if the audio CD doesn't play well, you need to check with your experienced computer techo whether either your internal computer configuration does not allow for high quality sound or
- if that's OK, then are your speakers high quality?
what's in front of you
modem
- your modem may be external (in a case outside your main computer 'box) or internal (slotted inside the main 'box')
- a modem is a telephone for a computer
- the modem modulates the information the computer is sending out
(basically fiddles with the output info until it fits what the modem at the other end can handle)
- it also compresses the information so it can be transferred more quickly
- but the first thing it has to do is
- ring up the other modem (using your connect script which includes the phone number)
- and do what's called handshaking, where it makes a variety of weird sounds while trying to find a workable connection with what is probably a totally different modem, possibly during bad phone conditions (frequent phone line problems, weather changes)
- and then go through the rest of your connect script, including your username and password for identification
- each modem comes with a manual, which explains the way it works and the progress or error messages it can send you
- modems are marketed in speeds of bps (bits per second) transferred
- 33.6k bps (33.6 thousand bits per second) has been the current standard although the
- 56.6k bps standard has now been agreed (all 56.6k modems will be upgradable to fit this standard -- see your modem manufacturer's website for details)
- bear in mind that the speed of the modem at the other end, the speed of the phone line in between, and of all the phone lines and links between your machine and another one (especially if it's busy and/or overseas), will affect the actual speed of information transfer
- modems vary in quality, reliability and performance --
as with any computer equipment,
get advice from an experienced computer technician before investing in something that might look flashy and be cheaper, but not do the job for you
what's in front of you
clytie@riverland.net.au
next article:glossary (part 2): information storage: ...bits, bytes and how to get the best out of your hard drive
back to 'Look Here First'
