A bar-joint framework is a structure made of fixed-length bars connected by joints with full rotational degrees of freedom. The allowed continuous motions preserve the lengths and connectivity of the bars. If all the allowed motions come from Euclidean isometries, the the framework is rigid and otherwise it is flexible. Combinatorial rigidity theory is concerned with how much geometric information about a framework (e.g., if it is rigid or what its motions are like) from just the graph that has as its edges the bars. In this talk, I'll introduce frameworks in more detail and discuss some basic results and techniques in the area.