Geometry is, along with arithmetic, one of the oldest branches of mathematics. A mathematician who works in the field of geometry is called a geometer.

Feb 2, 2026 · Geometry, the branch of mathematics concerned with the shape of individual objects, spatial relationships among various objects, and the properties of surrounding space.

Explore geometry concepts including angles, shapes, transformations, and proofs with Khan Academy's engaging resources.

Geometry is all about shapes and their properties. If you like playing with objects, or like drawing, then geometry is for you!

Essential stuff for describing the world around you. 1. Lines and angles. 2. Related angles. What about angles bigger than 360 degrees? 3. Triangles. See if it's really true, and then prove it! They have two …

Interactive, free online geometry tool from GeoGebra: create triangles, circles, angles, transformations and much more!

This Basic geometry and measurement course is a refresher of length, area, perimeter, volume, angle measure, and transformations of 2D and 3D figures. If you are learning the content for the first time, …