The man page continues: > This option can create a COW (copy on write) snapshot, or a thin snapshot (in a thin pool.) [...] COW snapshots are created when a s

The man page continues: > This option can create a COW (copy on write) snapshot, or a thin snapshot (in a thin pool.) [...] COW snapshots are created when a size is specified. The size is allocated from space in the VG, and is the amount of space that can be used for saving COW blocks as writes occur to the origin or snapshot. Likely snapshots _were_ originally read-only, and the description of creating thin and COW snapshots was added later, but the man page text was not re-written completely; rather the description of thin and COW snapshots were added to the end of the existing text.