A "heat" is a preliminary race in sports like track and field or swimming. Usually the winner of each "heat" advances to the "finals." A "round" has different meanings in different sports. For example, in golf it means 18 holes. In boxing, each of the "rounds" is timed and lasts three minutes. In team sports, each level of the playoff tournament is a "round" of the playoffs.

Hi Leticia. Can you give me an example of both? So I can see the context