Hull is designed to be used as the outside protective layer of ships in WarpDrive in conjunction with Hull Glass. There are three levels of Hull, each made from the earlier/weaker version: Basic, Advanced, and Superior.
Hull protects the ship from having parts of it destroyed when shot by lasers or colliding with other blocks. The difference in protection between each level is significant.
Note: While each level of Hull is made from the previous version, Hull Glass is only made from Hull and cannot be upgraded once created.
All types of hull can be colored with all of the vanilla minecraft colors. Each color gives the hull a different texture (all levels of Hull look the same):