The storage capacity of most CD-ROMs is about 650Mb of data. Originally CD-ROMS were read only devices, but now read/write technology has been developed.
Interface
Many CD-ROMs are interface to the computer using the ATAPI interface. This is ATA Packet Interface which is a IDE interface. This is designed for extra drives like CD-ROM's and tape drives that connect to an ATA connector. The ATAPI interface is the standard interface for IDE controlled CD-ROMS. If your CD-ROM uses an a ATAPI interface, it should be supported by all available software. If you are using a SCSI controller, you should probably use a SCSI CD-ROM. There are two primary types of CD-ROMs today.
Read only
Read and Write CD-ROM
These are primarily available as an internally mounted drive, but can also be purchased as an external device. There are some CD-ROM drives that interface through the parallel printer port.
Speed
The primary performance concern of CD-ROM drives is their speed. Speeds are expressed in terms of 1X, 2X, 4X, which is the number of times the drive is than the standard CD-ROM reader. Of the read only type, speeds have exceeded 50X. CD-ROMS of up to 40X speeds and beyond can be purchased today for a reasonably low price.
The read/write type of CD-ROM speeds are expressed with three values. They are read, write, and rewrite. Current speeds of these devices are 32X, 10X, 4X. Currently 32X by 8X by 4X are priced reasonably at around $220. This compares to a 40X read CD-ROM drive at around $30-40. Therefore we recommend you do not rely upon your read/write CD-ROM drive for reading normal CDs especially where playing games in concerned. You could wear out your expensive CD-ROM performing read operations which costs a great deal more than a read only CD-ROM!
