Polychoron

Graphs of six convex regular 4-polytope.
4-simplex (5-cell)	4-orthoplex (16-cell)	80px 4-cube (Tesseract)
24-cell	120-cell	80px 600-cell

File:Hypercube.svg

The tesseract is the best known polychoron, containing eight cubic cells, three around each edge.It is viewed here as a Schlegel diagram projection into 3-space, distorting the regularity, but keeping its topological continuity. The eighth cell projects into the volume of space exterior to the boundary.

In geometry, a polychoron (plural: polychora) is a figure in four dimensions. The word comes from Greek poly, which means many and choros which means room, or space. Sometimes the figure is called 4-polytope or polyhedroid. The analogue figure in two dimensions is a polygon, and the one in three dimensions is a polyhedron.

Polychoron Media

4-simplex graph
Tesseract//16-cell family graph in B4 Coxeter plane
Tesseract//16-cell family graph in B4 Coxeter plane
24-cell family polytopes in Coxeter plane symmetry
600-cell graph H4.svg

600-cell graph in H4 Coxeter plane
120-cell graph H4.svg

120-cell graph in H4 Coxeter plane
24cell section anim.gif

Animated cross section of a 24-cell. Shows the intersection of the 24-cell and a 3-D hyperplane as the hyperplane passes through the 24-cell from corner to corner.160x120 pixels, 21 frames, animated GIF.
Polychoron 24-cell net.png

Oolychoron_24-cell_net, en:Stella (software)
Schlegel wireframe 24-cell.png

Schlegel wireframe 24-cell
24-cell family polytopes in Coxeter plane symmetry

Other websites

Eric W. Weisstein, Polychoron at MathWorld.
Four dimensional figures page
Jonathan Bowers: Uniform polychora