what is cork cell ?

Cork cells are plant cells on the outer edge of the trunks of woody plants. It is a secondary tissue produced by the cork cambium, and forms the outer part of the periderm in a woody plant. They are dead cells and appear as empty hexagonal or pentagonal spaces under the microscope. Cell wall of cork cells contains suberin which makes it water resistant. These cells are filled with air and their major function is protection and waterproofing.