Definitions for "Unallocated space"
Available disk space that is not allocated to any partition, logical drive, or volume. The type of object you can create on unallocated space depends on the disk type (basic or dynamic). For basic disks, you can use unallocated space outside partitions to create primary or extended partitions. You can use free space inside an extended partition to create a logical drive. For dynamic disks, you can use unallocated space to create dynamic volumes. Unlike with basic disks, you do not select the exact disk region used to create the volume.
the set of clusters that has been marked as available to store information but have not yet received a file, or still contain some or all of a file marked as deleted.
Available disk space that is not allocated to any partition, logical drive, or volume. The type of object created on unallocated space depends on the disk type (basic or dynamic). For basic disks, unallocated space outside partitions can be used to create primary or extended partitions. Free space inside an extended partition can be used to create a logical drive. For dynamic disks, unallocated space can be used to create dynamic volumes. Unlike basic disks, the exact disk region used is not selected to create the volume. See also basic disk; dynamic disk; extended partition; logical drive; partition; primary partition; volume.