a logical construct, versus a physical one
a space on your hard disk that your operating system will treat as a different drive
A logical compartment on a physical disk drive. A single disk might have two or more logical disk partitions, each of which would be referenced with a different disk drive name. Multiple partitions are divided into a primary (boot) partition and one or more extended partitions.
The physical filesystem with a tangible physical location. Partition size determines the number of blocks that the filesystem uses.