The Triangular Prism
The triangular prism is a simple 3D uniform polyhedron bounded by 2 triangular faces and 3 squares. It has 9 edges and 6 vertices. It may be considered to be the extrusion of the triangle.
Two triangular prisms can be glued together at their square faces in gyro orientation to produce a gyrobifastigium (J26), a Johnson solid:
Projections
In order to be able to identify the triangular prism in various projections of 4D objects, it is useful to know how it appears from various viewpoints. The following are some of the commonlyencountered views:
Projection  Envelope  Description 

Triangle  Parallel projection centered on a triangular face. 

Square  Parallel projection centered on a vertical edge. 

Rectangle  Parallel projection parallel to a square face. The left edge of the projection is the image of a square face. 

Nonuniform pentagon  Vertexcentered parallel projection. 
Coordinates
The Cartesian coordinates of the triangular prism, centered on the origin and having edge length 2, are:
 (−1, −1/√3, ±1)
 (1, −1/√3, ±1)
 (0, 2/√3, ±1)
Occurrences
The triangular prism is a very versatile polyhedron that occurs in many 4D uniform polytopes, including:
 The cantellated 5cell;
 The runcinated 5cell;
 The cantitruncated 5cell;
 The runcitruncated 5cell;
 The cantellated tesseract;
 The runcinated tesseract;
 The cantitruncated tesseract;
 The runcitruncated tesseract;
 The cantellated 24cell;
 The runcinated 24cell;
 The cantitruncated 24cell;
 The runcitruncated 24cell;
 The cantellated 120cell;
 The runcinated 120cell;
 The cantitruncated 120cell;
 The runcitruncated 120cell;
 The 3,nduoprisms, such as the 3,3duoprism and the 3,4duoprism.
It also occurs in many CRF polychora, including (but not limited to):