Hull is the basic building component of every ship, in every faction. ( Regardless of what it might be named. )
Hull is essentially a geometric block that is used mainly to create the body of a ship or station. Hull acts as a source of Health, with no Power cost, but has Mass which weighs the ship down.
Most hull can be scaled up to different sizes, with health and weight equal to their equivalent in any combination of smaller blocks.
Other races' hull are named alternatively, such as "Strut", "Segment", "Bodywork", "Crystallite" or "Penrose".
The Crystallite is a type of default hull building block for the Faction 11, these hulls has up to 4 different scales that you can build, their shapes through consist of diamonds, triangles, isoscales shapes designs for fitting together with pentagon and rhombus parts.
Pentroses are the hull components of Faction 3, they come in two shapes, both parallelograms/diamonds, somewhat like the Crystallite of faction 11.