The perimeter is the distance around the outside of a 2D shape. The distance can be measured in units like millimetres, centimetres, metres and kilometres. To work out the perimeter, add up the ...

Attention type nerds, did you know there are online games just for you? It's true, Shape Type is a new HTML5 typography game where you have to drag curve-adjustment tools to perfect letterforms in ...

2D shapes can be described by their sides, their angles and their symmetry. The sides might be equal in length and some might be parallel. The angles could be right angles, but sometimes they are ...