Unicursal - Maze without branches. Sometimes called a circuit maze.
Multicursal - Maze with branches and dead ends.
Blind Alley- Branch that is a dead end.
Island - Asection of the maze containing walls not connected to the external wall of the maze. Sometimes also referred to as a detached wall.
Theta - A type of maze composed of concentric circles.
Braid Maze - A type of maze with branches, but without dead ends. All branches loop back to other branches.
Perfect Maze - Maze with no islands or isolated sections. A perfect maze has only one solution.
Delta Maze - Maze consisting of interlocking triangles.
Plainair Maze - A maze on something other than a flat surface. For example, a maze painted on the outside of a cube or sphere.
Source: The UnMuseum