A partition is just that. A dedicated sectioning of a harddisc. A HDD can have up to 4 primary partitions and up to 24 logical partitions based on the archetecture of the operating system.

The differences are that primary drives are made as bootable (active) and are given a priority for assigned drive letters than what logical partitions are given.

To change the logical to primary (bootable) ......while in disc management
in the lower window rt. clk. the partition that you wish to change and select "make active".