Geometry is a branch of mathematics that studies shapes, sizes, positions, and properties of space. It explores points, lines, angles, surfaces, and solids, as well as their relationships and transformations. From basic concepts like circles and triangles to advanced topics such as coordinate geometry and topology, it provides tools for measuring and analyzing spatial forms. Euclidean geometry, founded by the ancient Greek mathematician Euclid, remains fundamental, dealing with flat shapes and theorems like the Pythagorean theorem. Other branches include analytic geometry, which uses algebra to solve geometric problems, and differential geometry, which applies calculus to curves and surfaces. Geometry is essential in fields like architecture, engineering, physics, and computer graphics, helping solve real-world problems through precise spatial reasoning.