Definitions for "Primary partition"
A partition that is used to start an operating system. Primary partitions are partitions that take up one of the four primary partition slots in the disk drive's partition table. You can also use primary partitions that do not contain the operating system.
A volume you create using unallocated space on a basic disk. Microsoft Windows NT and other operating systems can start from a primary partition. You can create up to four primary partitions on a basic disk, or three primary partitions and an extended partition. Primary partitions can be created only on basic disks and cannot be subpartitioned. See also Basic disk, Dynamic volume, Extended partition, Partition.
A partition on a hard drive that is used to boot up the computer. It is the first partition that is created on the hard drive.