A circular region or a disk.
A flat circular object is called a disk or a round.
A circular scratch on a game disk most often comes from a defective disk drive. It usually means that whatever device read the disk had an ojbect stuck in the disk drive that did not belong there or that the drive is not perfectly suspending the disk above the reader. The drive spins your disk around inside the Xbox and if something is sticking up in there or if the disk is leaning to the side and it rubs against something while spining, it will put that kind of scratch on the disk.
Hard Drive
It doesn't stand for anything. It's a component/s inside your Hard Disk Drive (HDD). When you save data or install programs on your computer, the information is typically written to your Hard Disk. The Hard Disk is a spindle of magnetic disks called platters. The Hard Disk is housed inside the Hard Drive, which reads and writes data to the disk.
Its called your hard drive.
a hard drive is called "disque dur" in French.
Turbine
Floppy drives and CD/DVD roms are examples of removable disks because the storage medium is removed from the drive. A hard drive has a set of magnetic platters that you do not remove, making it a fixed disk.
A hard disk that is inside your own PC as opposed to a hard drive you are accessing on a network, that would be in another PC somewhere else.
Correction: the "A" Drive is a floppy disk dirve that holds, reads and writes on the floppy disk.
because is a fixed drive