So you're running out of space and you need some more. Or maybe you just want to make your own CD's or back-up data. Well, here's how you can do it.
First, lets talk about hard drives. These are large capicity storage devices that are found inside your computer. If you want, you can buy a new one to replace the one already in your computer (probably an ATA hard disk). ATA's are relatively cheap, but you lose evrything that you had on your old drive (unless you back it up on CD's or ZIP's). The more practical thing to do, is to buy either a SCSI or USB hard drive. The only difference is that USB's are faster and can only be external (more details about difference). A SCSI internal hard drive would fit inside your computer next to the floppy or CD-ROM drive if you have a empty slot big enough; check the documentation that came with you computer to find out if you do. External SCSI and USB hard drives would sit outside your computer and plug into SCSI chain or USB port. Externals are a little more expensive than internals.
An alternative is removable media such as Zip drives and Jaz drives. These disks (kind of like floppy disks) hold large amounts of data and work much faster than floppies. They are a great for backing up files and transfering large amounts of data between computers. The original ZIP drive could support 100 MB disks; the new ZIP drive can support 100 MB and 250 MB disks. If you buy a zip drive, be sure to check which model you're getting. Some computers come with a built in Zip drive (part of the SCSI chain). Jaz drives support 1 GB and 2 GB disks; Jazz drives are more expensive but are a great way to expand your storage space. Both come as internal or external and as SCSI or USB (see above).
CD-R (CD Recorders, also known as CD burners) and CD-RW (CD ReWritable) each use a different special CD that can hold 650 MB of data or 74 minutes of music. The only difference (except price) between the two drives is that CD-R's can only record onto the empty space on a CD (it can't delete or over-write data) whereas a CD-RW can over-write and delete data from a CD. Some CD-ROM drives have trouble with "burned" CD's but CD-R's and CD-RW's are mostly compatible. The drives can come as internal or external and as SCSI or USB (see above). They should also come with all the necessary software for making your own CD's. If you just got to make your own CD's, buy one of these.
DVD and CD-ROM drives can be internal SCSI or external SCSI or USB (see above). Some computers come with one installed. DVD drives are fairly expensive because it is both a special reader and decoder. It can use both DVD data and Movie disks as well as regular data and audio CD's. CD-ROM drives only recognize CD's, not DVD's. Both will come with any software and drivers that you may need. There aren't many DVD drives for Mac; as they become available I will list them.