**
AA
** -
A method for proving similarity of triangles: if two angles are
congruent to their
corresponding parts in another triangle, then the triangles are similar.

**
AAS
** -
A method for proving congruence of triangles: if two angles
and a side not
included by those angles are congruent to their corresponding parts in
another triangle, then the triangles are congruent.

**
ASA
** -
A method for proving congruence of triangles: if two angles
and their
included side are congruent to their corresponding parts in another
triangle, then the triangles are congruent.

**
Congruent Triangles
** -
Triangles whose corresponding angles and sides are all congruent.

**
Congruent Polygons
** -
Polygons whose corresponding sides and interior angles are all
congruent.

**
Corresponding Parts
** -
The angles or sides in a polygon organized such that each angle and each side
coincides with exactly one angle or side in another polygon--the pairs of angles
and sides in each polygon are called corresponding parts.

**
Hypotenuse-Leg
** -
A method for proving congruence of
right triangles: if one
leg and the
hypotenuse are congruent to their
corresponding parts in another right triangle, the right triangles are
congruent.

**
SAS
** -
A method for proving congruence or similarity of
triangles: if two sides
are congruent or proportional and their included angle is congruent to their
corresponding parts of another triangle, then the triangles are congruent or
similar, respectively.

**
Similar Triangles
** -
Triangles whose corresponding angles are
congruent and whose corresponding sides are
proportional. Congruence is a subset of similarity.

**
SSS
** -
A method for proving the congruence or similarity of
triangles: if the
three sides of a triangle are congruent to their corresponding parts, then
the triangles are congruent. If the three sides of a triangle are proportional
to their corresponding parts in another triangle, then the triangles are
similar.