In this situation, the partitions already defined do not span the entire hard disk, leaving unallocated space that is not part of any defined partition. Figure D.8, “Disk Drive with Unpartitioned Free Space”, shows what this might look like.

In Figure D.8, “Disk Drive with Unpartitioned Free Space”, 1 represents an undefined partition with unallocated space and 2 represents a defined partition with allocated space.

If you think about it, an unused hard disk also falls into this category. The only difference is that all the space is not part of any defined partition.

Next, we will discuss a slightly more common situation.