Computer
Hardware
General
classes of hardware :
- Input - used
to get information into the computer. Includes keyboard, mouse, scanner, digitizer,
digital camera, etc.
- Output - used
to get information out of the computer. Includes monitor, printer, plotter
- CPU
- Central Processing Unit.
The brains of the computer - where the processing takes place.
- RAM. Random
Access Memory. Think of this as the active memory of the computer. Temporarily
stores program instructions and data. The more RAM, the more stuff your
computer can handle at once. Turn the computer off, and you lose everything
that's in memory. For perspective, Vista systems require at least 2 GB
of RAM, however, it is recommended that you purchase 4 (the max Vista
can use).
- ROM - Read
Only Memory. This is your permanent memory. It stores the information
required to boot up the computer.
- Processor.
This does the work. It gets info from RAM, changes it, and sends it back
to RAM - where it can be accessed by the monitor or stored to a mass storage
device.
- Video card
- this is the beastie that displays stuff on screen. It usually has it's
own RAM to do the work. If you're a gamer, a 256 mb 3D chip will do what
you need - at least this year. Beware those that are built into your motherboard
- they cannot be upgraded. Thus, if purchasing a computer with a built-in
video card, make sure the motherboard also has an AGP slot (where you
can install your own video card). In the graphics world, including both
gaming and GIS, be sure to buy systems with powerful graphics cards.
- Bus speed:
effectively how fast your computer can shuffle information from processor
to RAM to video to harddrive, etc.. Most current systems are 32 bit -
newer ones are 64. Beware 8/16 bit systems - they won't run much these
days.
- Mass storage:
Where you store your files. Harddrives (as of July, 2008, 1000 GB drives are
available), CD (640 MB), floppy (1.44mb), DVD (up to 9 gb), Blu-ray DVD (25
GB), zip disks (100/250/750 mb), tape drives, etc... There are many many,
many different ways of storing data - these are only the most common. Note,
tape drives have become less and less common, zips are almost completely obsolete,
floppys are useless, and most folks use USB flash drives as their portable
storage medium.
Ports
on back of computer
- Parallel. slow.
typically, this is your printer port. being phased out. Newer computers no
longer have them. Replaced by USB
- Serial. slow.
being phased out. Now phased out, plug stuff into USB.
- SCSI. A fast
connection, usually requiring a SCSI card being installed in your computer.
Generates excess heat and are expensive. Pretty much obsolete these days.
- PCMCIA. Credit
card sized cards plug into PCMCIA ports - usually found on laptops. Slowly
being phased out, but you can still buy PCMCIA hardware.
- Video - this
is where you plug in your monitor.
- PS2 - mouse/keyboard
ports. Also being phased out. Again, gone on new computers. Replaced by USB.
- USB. The new
standard for just about everything. Fast, simple.
- Firewire. The
competitor to USB. Also very fast. Usually only found on Macs. Typically,
firewire is a little faster than USB.