Here are some snapshots taken from a Graphing calculator.
This is a software which runs both on Windows and OS X. A Viewer is free. There is an educational
version. Note that OS X comes with a graphing calculator too. You find it in Applications/Utilities.
It is not as powerful as the graphing calculator itself.
Here is the story, on how the program was developed.
Graphing calculators are fun to play with.
They are simple to use, but never have the possibilities like a computer algebra system.
The following animations and pictures have been grabed directly from the screen under OS X.