Solid geometry

Solid geometry studies three-dimensional figures and their properties, measurements, and relationships in space. It includes shapes with flat faces and curved surfaces.

Euclidean space: A geometric space in which points, lines, distances, and angles obey Euclidean geometry. Solid geometry usually treats figures as subsets of ordinary three-dimensional Euclidean space.
Three-dimensional coordinate system: A system that locates points in space using three numerical coordinates. Coordinates turn spatial positions into quantities that can be calculated.
Platonic solid: A convex polyhedron whose faces are congruent regular polygons meeting identically at every vertex. These five highly symmetric polyhedra are foundational examples of solids.
Plane geometry: The branch of geometry that studies figures confined to a two-dimensional plane. It restricts geometric questions to two dimensions rather than space.
Point: An exact location with no dimensions. Points locate vertices and define the positions of figures in space.
Distance formula: A formula for finding the straight-line distance between points from their coordinates. It measures lengths between vertices and other points in space.
Prism (geometry): A polyhedron with two congruent, parallel polygonal bases joined by parallelogram faces. Prisms illustrate how a repeated cross-section determines a solid's form.
Analytic geometry: The study of geometry using algebraic equations and coordinate systems. It provides an algebraic method for solving spatial problems.
Plane: A flat, two-dimensional surface extending without bound. Planes contain faces and cross-sections of three-dimensional figures.
Dihedral angle: The angle between two planes, measured in a plane perpendicular to their intersection. It quantifies how adjacent faces meet along an edge.

Linked from 2 pages

Commandino's theoremNarrower topic: Commandino's theorem belongs to the long study of solid measurement.