D: is a PC drive letter often assigned to the CD-ROM or other disc drive. Computers with one hard drive and partition automatically assign the CD-ROM or other disc drive as the D: drive. However, this drive can be any drive letter, but is often assigned as the last physical drive letter. The picture below is an example of the DVD-RW drive, which is assigned as the E: drive.

A:, C:, CD terms, Drive letter

See our drive definition for a full listing of other drives.

  • How to change a drive letter.
  • How to rename or label a disk drive.
  • Why is my CD-ROM drive not the D: drive?
  • CD-ROM help and support.