The "Group Stage" is a preliminary round in various sports tournaments, including the FIFA World Cup and UEFA Champions League. During this phase, teams are divided into groups, where they compete against each other in a round-robin format. Each team plays every other team in its group, earning points for wins and draws. The top teams from each group typically advance to the knockout stage of the tournament. The Group Stage helps determine which teams are the strongest and sets the stage for more intense competition in the later rounds.