Section 6: Scoring

Rule 3.1: A goal is scored when the ball is played over the goal-line, between the posts and under the crossbar, by either team. A point is scored when the ball is played over the crossbar, between the posts, by either team.

Source: Rule 3.1, Rule 3.2, Rule 3.3, Rule 3.4, Rule 3.5, Rule 2.9

Send this to your friend — argument over.