The CD-ROM Technically Speaking
The physical parameters of CD-ROMs are identical to those defined in the Red Book. The use of the data it contains is different. While audio CDs can be played at only one speed, CD-ROM drives exist with a range of speed options from normal (1x) to four times normal speed (4x) and so on and now 52x. As the speed increases the access time decreases.

CD-ROM discs differ from CD audio discs in two important ways.

The data on a CD-ROM disc are divided into sectors which contain both user data and other data for control and (additional) error protection. The data on a CD-ROM are contained in files. All CD-ROMs therefore, need a file system to enable the computer to access the required file easily and quickly.

Storage capacity of our CD-ROMs
682 Mbytes* of user data in CD-ROM mode 1 (2048 bytes/record) OR up to 78 minutes of digital audio @44.1Khz OR a combination of the above (enhanced CD).

CD-ROM Input Specification
The CD-ROM specification is defined in the Yellow Book which is based on the CD audio format but for computer data. The salient parameters are shown below:

Parameter	Value	Comments
Data capacity	682 MB	74 minutes
Raw data bit rate	1.41Mb/s	all bytes
User data rate	150 kB/s	at normal speed
Block (sector) size	2352 bytes
User data per sector	2048 bytes full error correction
Sector rate	75 sect/s	at normal speed
Sector Modes	1 or 2
Sector Forms	1 or 2	only with Mode 2

You must use "Disk at Once Mode" when burning your data onto CD-R. Do not attempt to send us masters using "Track Incremental" or "burn session". Disc at once mode finalizes the disc and prevents further additional data recording.