Complex sentence: Greedy colorings do not in general use the minimum number of colors possible; however they have been used in mathematics as a technique for proving other results about colorings and in computer science as a heuristic to find colorings with few colors.
Split into simpler sentences: Greedy colorings do not in general use the minimum number of colors possible. However, they have been used in mathematics as a technique for proving other results about colorings and in computer science as a heuristic to find colorings with few colors.