For them, it’s the cumulative score over four rounds which decides the winner, with the lowest total taking the prize. In the event of a tie there is usually a playoff over a pre-determined number of holes, or until one of the competitors beats the score of his opponent/s on any given hole.
Within golf clubs, strokeplay is used for ‘medal’ competitions, usually held once a month, but in these, unlike the professional tours, handicaps are applied and it is nett scores that are counted. So if a 10 handicapper shoots gross 81 over a par 72 course, his nett score is 71 (81 minus 10). If his fellow competitor with a one handicap shoots a gross 73, his nett score is 72 (73 minus one) and he loses to the 10 handicapper.