A hard drive is a storage device located inside the computer. It is called hard drive because the disks are located inside the box. The disks inside cannot be removed as in case of a floppy drive.
Like a floppy disk, hard drives also store programs and data. A hard disk stores more data than a floppy disk and is more stable when compared to floppy drives.
Like RAM, hard-drive capacity is also measured in megabytes. Since most new hard drives have capacities of over 1000 megabytes, the capacities are measured in gigabytes, equaling roughly 1000 megabytes.
Many computers might have an IDE, SCSI or both installed. SCSI and IDE drives look quite similar. They are both about the same size as a floppy drive. The IDE cable has a 40-pin connector and is about 1.5 inches wide. The SCSI drives use a 2-inch-wide cable and 50-pin connector.
Another important device of storage is the CD-ROM.
