http://www.geogebra.at/

GeoGebra is a dynamic mathematics software that joins geometry, algebra and calculus.

• On the one hand, GeoGebra is a dynamic geometry system. You can do constructions with points, vectors, segments, lines, conic sections as well as functions and change them dynamically afterwards.
• On the other hand, equations and coordinates can be entered directly. Thus, GeoGebra has the ability to deal with variables for numbers, vectors and points, finds derivatives and integrals of functions and offers commands like Root or Extremum.

It is developed for education in secondary schools by Markus Hohenwarter at the University of Salzburg.

GeoGebra received several international awards including the European and German educational software awards.