Definition: A partition can be thought of as a division or "part" of a real hard disk drive. When you partition a hard drive, you make it available to an operating system. Multiple partitions on a singe hard drive appear as separate drives to the operating system.
For example, when you install an operating system like Windows 8, part of the process is to define a partition on the hard drive. This partition serves to define an area of the hard drive that Windows 7 can use to install all of its files. In Windows operating systems, this primary partition is usually assigned the drive letter of "C".
Also Known As: disk partition, drive
Examples: "When I reinstalled Windows 7, I had to remove the existing partition and then create a new one for Windows to install on."