| Criterion | Description |
|-----------+-------------------------------------------------|
| SSS | All three corresponding sides are same. |
|-----------+-------------------------------------------------|
| SAS | Two corresponding sides |
| | *and the angle between them* are same. |
|-----------+-------------------------------------------------|
| ASA | Two corresponding angles |
| | and the side between them are same. |
|-----------+-------------------------------------------------|
| AAS | Two corresponding angles |
| | and an angle that is not between them are same. |
|-----------+-------------------------------------------------|
| HL | For right triangles, if hypotenuse |
| | and one other side are same. |
(SSA is doesn't always hold and can't be used generally)
| Criterion | Description |
|-----------+-------------------------------------------|
| AA | Two corresponding angles are same. |
|-----------+-------------------------------------------|
| SSS | All corresponding sides are proportional. |
|-----------+-------------------------------------------|
| SAS | Two corresponding sides are proportional, |
| | and the angle between them are same. |
In the case of similarity criteria, when two side are proportional, the constant of proportion should be same as well.
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Reference: Khan Academy