A
parallelepiped, also (incorrectly) called
parallelopiped, is a 3-dimensional
polyhedron with six
parallelograms for faces.
The word is also sometimes used for the higher-dimensional analogues.
All opposite faces are parallel. The
volume of a parallelepiped can be calculated most easily using
determinants.
All Wikipedia text
is available under the
terms of the GNU Free Documentation License