Unless you came to this site by complete accident, you might already know that SCSI stands for Small Computer System Interface, and it's pronounced "skuzzy".  SCSI's primary function is to provide a means for your computer to access devices (get/store data) throughout the computer.  The system that probably came with your computer is called IDE (Integrated Drive Electronics).  They both accomplish the same thing, just with different methods.

So what can SCSI do for you?  With a SCSI setup you can hook just about any kind of device up to your computer, including hard drives, tape drives, CD-ROM's, CD burners, DVD drives, floppy drives, scanners, cases, and a bunch of other crap I wouldn't know about.  As long as a few changes are made to the device and its drivers, it can be used in a SCSI system.

So what do you need if you want use SCSI?  Well, first you need a way for all your SCSI devices to interface with the rest of your computer.  You need a special card that can be called several things, including Controller or Adapter.  I'll be interchanging the two throughout.  Next, you'll need some sort of cabling to go from your controller (or adapter) to your SCSI devices.  What a surprise, huh?  Besides a few minor odds and ends, that's all you'll need for a SCSI setup.

So what would a SCSI setup look like?  From the outside it isn't too much different from an IDE interface.  In the old days, motherboards didn't come with on-board IDE controllers.  If you wanted to have a hard drive you had to buy a separate IDE controller card.  This is about where SCSI is for home users, but some higher-end motherboards are shipping with built-in SCSI controllers.  If you'll look inside your computer right now, you'll see one or two wide gray cables coming out of your hard drive(s) and your CD- ROM.  These are plugged into wide sockets on your motherboard.  If you imagine these plugs on a separate card, like your video card, that's pretty much what a typical SCSI system would look like.

Here's a typical IDE system, messily drawn in Paint Shop Pro

As you can see, the devices are "daisy-chained" together, that is, the two devices use the same cable to interface to the computer.  A SCSI system will work in a very similar manner.  Here's an example of one:

Notice how there are more than two devices on each cable, unlike the IDE example.  This is one of SCSI's big advantages, having more than two devices on a cable  For a low-end SCSI setup, you can have up to 8 devices on a single cable.  As you climb up the technology (and cost) ladder, it's possible to have 15 or 31 devices on a cable!

Here's a picture of the inside of my case, with the SCSI and IDE cables pointed out.  You can't see the SCSI hard drive or burner, but we'll get to those parts in the hardware section.

We might as well go onto the Configuration section to see how to setup SCSI devices.