The Geometer's Sketchpad is an interactive mathematics software program that helps students to visualize and explore mathematical concepts. It is designed to be used in the classroom and at home, as a supplement to lectures or textbooks. With the Sketchpad, students can explore geometry, algebra, trigonometry, and calculus in an intuitive and visual way. Using the powerful tools of the software, students can construct diagrams, sketches, and animations to illustrate their understanding of mathematical concepts. The Sketchpad also allows users to work with multiple representations of the same mathematical object, using the integrated dynamic geometry environment. With this feature, users can explore the relationships between geometric shapes, explore how changes to one shape affect other shapes, and create animations to illustrate the changes. The Geometer’s Sketchpad is a great way to help students learn mathematics in a more engaging and interactive way.
The latest discontinued version is 4.4.2 (2013) https://sourceforge.net/projects/graph/files/Graph/