How does one draw a parallelepiped in Mathematica?

Question

I'm a bit new to the application, and I'm not sure how to draw a parallelepiped in Mathematica.

Answer 1

Right from the documentation of ShearingMatrix, that is a GeometricTransformation:

Graphics3D[{GeometricTransformation[{Opacity[.85], Red, Cuboid[]}, 
   ShearingMatrix[Pi/4, {1, 0, 0}, {-1, 1, 0}]]}, Boxed -> False]

A dynamic manipulator to understand arguments:

Manipulate[
 Graphics3D[{
   GeometricTransformation[{Opacity[.85], Red, Cuboid[]}, 
    ShearingMatrix[a, dir, {x, y, z}]]
   }, FaceGrids -> {{-1, 0, 0}, {0, 1, 0}, {0, 0, -1}}, Axes -> True, 
  Boxed -> False, BoxRatios -> 1, SphericalRegion -> True],

 {{a, Pi/4}, -Pi/2, Pi/2, Appearance -> "Labeled"},
 {{dir, {0, 1, 0}, "direction"}, {{1, 0, 0}, {0, 1, 0}, {0, 0, 1}}},
 {{x, -1}, -1, 1, .1, Appearance -> "Labeled"},
 {{y, 1}, -1, 1, .1, Appearance -> "Labeled"},
 {{z, 0}, -1, 1, .1, Appearance -> "Labeled"},
 ControlPlacement -> Left
 ]