Triangle congruence refers to the concept that two triangles are congruent if they have the same size and shape. This means that all corresponding sides and angles of the triangles are equal. There are several methods to determine triangle congruence, including the Side-Side-Side (SSS) criterion, the Side-Angle-Side (SAS) criterion, and the Angle-Side-Angle (ASA) criterion. In practical terms, if you can show that two triangles meet any of these criteria, you can conclude that they are congruent. This concept is fundamental in geometry and is used in various applications, such as in construction, design, and mathematics.