Congruence is a term used in mathematics to describe a harmonious relation, agreement, or correspondence between two objects or shapes. The term "congruent" means exactly equal in shape and size, and this shape and size should remain equal even when we flip, turn, or rotate the shapes. Congruence can be applied to line segments, angles, and figures. Two figures are said to be congruent if they can be placed precisely over each other. In geometry, two triangles are congruent if all three corresponding sides are equal and all three corresponding angles are equal in measure. The properties of congruence are applicable to lines, angles, and figures, and they can be listed as follows: reflexive property, symmetric property, and transitive property. Congruence is represented by the symbol "≅," which is made of two symbols, one above the other. The symbol of tilde "~" represents similarity in shape, and "=" represents equality in size.