The ones on the right contain some exterior angles that are less than 180 degrees, giving them concavity. Not every exterior angle of these shapes is this way, but due to having some exterior angles like this, I called them concave. The ones on the left have none of these such angles.
The convex ones are concave on the other side. The straight piece is generally called “the straight piece”
deleted by creator
The ones on the right contain some exterior angles that are less than 180 degrees, giving them concavity. Not every exterior angle of these shapes is this way, but due to having some exterior angles like this, I called them concave. The ones on the left have none of these such angles.
I agree with calling a straight a straight.