Occurrence of the Conics
- Images of conics by Jill Britton.
- http://britton.disted.camosun.bc.ca/jbconics.htm

Tim's Triangular Page
- Explains the basic properties, formulas, theorems and different types of triangles. Includes proofs and illustrations.
- http://sakharov.net/triangle.html

Polygons
- Discusses the differences between the different types of these straight sided figures. Also, explains the difference between regular and irregular shapes.
- http://www.ul.ie/~cahird/polyhedronmode/polygons.htm

Xah: Visual Dictionary of Special Plane Curves
- A Visual Dictionary of Special Plane Curves with graphics.
- http://www.xahlee.org/SpecialPlaneCurves_dir/specialPlaneCurves.html

Pythagorean Theorem
- A collection of 43 proofs - some interactive - of the Pythagorean theorem.
- http://www.cut-the-knot.org/pythagoras/index.shtml