To summarise:
brush = zero or more (upto 8) texture layers + color (& more)
surface = vertices + triangles + brush
mesh = one or more surface(s)
entity = heirarchy of meshes/pivots/bones/lights etc
brush = zero or more (upto 8) texture layers + color (& more)
surface = vertices + triangles + brush
mesh = one or more surface(s)
entity = heirarchy of meshes/pivots/bones/lights etc