[1] The level of performance is typically measured in tournament performance rating above a certain threshold (for instance, 2600 for GM norm), and there is a requirement on the level of tournament, for instance by a prescribed minimal number of participants of given title/level one meets.
To qualify for the title of Grandmaster (GM) of chess, a title awarded by FIDE, the World Chess Federation, a player must achieve three or more grandmaster norms in events covering a minimum of 27 games.
Norms can only be gained in tournaments that fulfill FIDE's strict criteria: for instance, the entry must include at least three GM titled players from different countries playing over a minimum of nine rounds with not less than 120 minutes thinking time per round, assuming the game lasts 60 moves (so for instance 90 minutes + 30 seconds per move qualifies).
The norm seeker must achieve a tournament performance rating (TPR) of at least 2600 to qualify.
This system requires five norms in order to achieve titles at seven different levels, ranking from "Life Senior Master" down to "4th category".