The cd drive commonly refers to the disc tray mounted at the top of your laptop.
CD drives were one of the earliest mass storage devices often used for accessing data on a computer. It was because they could hold so much information and were so inexpensive, even though their performance was not very fast and could only read CD-ROMs, that this type of medium became popular. However, it’s been many years since anyone has made use of them in newer computers due to an overwhelming preference for having hard disk space because you can add as much power (capacity) that way without adding weight or bulk as with disks.