In American and Canadian football, a two-point conversion is a play a team attempts instead of kicking a one-point convert immediately after it scores a touchdown. In a two-point conversion attempt, the team that just scored must run a play from close to the opponent's goal line (5-yard line in Canadian, 3-yard line in amateur American, 2-yard line in professional American) and advance the ball across the goal line in the same manner as if they were scoring a touchdown. If the team succeeds, it earns two additional points on top of the six points for the touchdown. If the team fails, no additional points are scored. In either case, the team proceeds to a kickoff.
Various sources estimate the success rate of a two-point conversion to be between 40% and 55%, significantly lower than that of the extra point, though if the higher value is to be believed, a higher expected value is achieved through the two-point conversion than the extra point.
Goal refers to a method of scoring in many sports. It can also refer to the physical structure or area of the playing surface where scoring occurs.
In several sports, a goal is the sole method of scoring, and thus the final score is expressed in the total number of goals scored by each team. In other sports, a goal may be one of several scoring methods, and thus may be worth a different set number of points than the others. A few of these sports use the term field goal to distinguish one scoring method from another.