[2] Most are DGEs: software that allows the user to manipulate ("drag") the geometric object into different shapes or positions.
supports macros, line segments, calculations, arbitrary functions, plots, etc.
This approach stresses the fact that geometrical constructions are abstract, formal procedures and not figures.
WinGCLC is a Windows version of GCLC with a graphical interface that provides a range of additional functionalities.
GeoGebra is software that combines geometry, algebra and calculus for mathematics education in schools and universities.
GeoKone allows the user to create geometric figures using naturalistic rules of recursive copying, such as the Golden ratio.
It emphasises use with a Computer Algebra System (CAS), as well as exporting and sharing via interactive HTML5, Lua and OS X dashboard widget apps.
The Geometer's Sketchpad (GSP) The Geometric Supposer[10] Geonext was developed by the University of Bayreuth until 2007 and is completely implemented in Java.
GeoProof[11] is a free GPL dynamic geometry software, written in OCaml.
GRACE (The Graphical Ruler And Compass Editor) is an analog of The Geometer's Sketchpad (GSP), written in Java.
Kig is a free (GPL) analog of The Geometer's Sketchpad (GSP) for KDE, but more calculus-oriented.
Live Geometry is a free CodePlex project that lets you create interactive ruler and compass constructions and experiment with them.
The core engine is a flexible and extensible framework that allows easy addition of new figure types and features.
The project has two front-ends: WPF and Silverlight, which both share the common DynamicGeometry library.
This is the nine-point circle, it intersects each side of the original triangle at two points: the base of altitude and midpoint.