Stable envelopes are canonical classes in the equivariant cohomology, K-theory, or elliptic cohomology of certain varieties that lie at the intersection of several different areas. They are important objects in physics, representation theory, enumerative geometry, and the combinatorics of symmetric functions. In the first part of this talk, I will survey various aspects of stable envelopes, discussing their definition, existence, and applications. Then I will present a recently obtained combinatorial formula for elliptic stable envelopes of type A quiver varieties. I will show examples of a Maple package I have written implementing these formulas.