This video appears on the page: Congruent Triangles–SSS, SAS, AAS, ASA, H-L

Everything You Need To Know About Congruent Triangles

Okay, not everything. More like the basics, the nuts and bolts, that form the foundation of all the theorems to come: what does congruent mean, what are corresponding parts, how am I supposed to draw those little congruency mark hashtag things on sides and angles, etc.