Hinged Tessellation
A tessellation which can be thought of consisting of a number of pieces which are hinged
at their vertices and therefore can be opened or closed to yield a series of tessellations.
Each blue square is hinged at its vertices so that the tessellation changes as any blue square is rotated.
Screencast
Screenr is a web-based tool to create screencasts without installing any software.
Source: screenr.com
A screencast is a recording of computer screen output, also known as a video screen capture.
Dynamic Geometry
You can alter the figure above
dynamically in order to test and prove (or disproved)
conjectures and gain mathematical insight that is less readily
available with static drawings by hand.
