A grind is the geometry of how the blade is taken from full thickness down toward the edge. Flat, hollow, sabre and convex are the four common ones, and the choice affects cutting performance more than the steel does.
Flat is a straight taper. Hollow is concave, ground on a wheel. Sabre starts the bevel partway down the blade instead of at the spine. Convex bulges outward in a curve.
A blade can combine them. A compound grind uses one geometry high on the blade and another near the edge.
Steel choice decides how long an edge lasts and how much abuse it tolerates. Grind decides how the blade feels in every single cut, because it determines how much material has to be pushed aside behind the apex.
A thin flat grind in a modest steel will out-cut a thick sabre grind in a premium steel every time. Read the grind before you read the steel name.