Geometry theorems are statements that have been proven to be true based on previously established facts, definitions, and axioms. They serve as fundamental building blocks in the study of geometry, helping to explain relationships between different shapes and angles. Theorems often provide formulas for calculating areas, volumes, and other properties of geometric figures. Some well-known examples of geometry theorems include the Pythagorean Theorem, which relates the sides of a right triangle, and Euclid's postulates, which form the basis of plane geometry. These theorems are essential for solving problems and understanding the properties of various geometric shapes.