Although there are several ways a team can score points in football, a team's ultimate goal is to cross the end zone and score a touchdown. A touchdown is worth six points and it is the scoring method that awards the most points. After scoring a touchdown, the team gets a chance to try a one or two-point conversion, where the ball is placed at the fifteen yard line and the team can either kick it between the posts, which is worth one point, or try to score two points by crossing the end zone with the ball again.
Since trying a two-point conversion can be rather risky, and the kickers rarely miss and extra point conversion, there is a common misconception that touchdowns are worth seven points because teams usually get 7 points in a drive that results in a touchdown.
In the first set of football rules created in the late 1800s, the only way to score was by kicking the ball between the goalposts. A goal was worth four points. That would soon evolve into a new set of rules where touchdowns and safeties were added as new ways to score, those were ways to make the game more fast-paced and exciting, the same reason why their value increased over time.
However, scoring a field goal was still the main goal, and it awarded more points than a touchdown. Finally, in 1909, the field goal was reduced to three points as we know today, while a touchdown was worth five. In 1912, the system became the way it is today, where touchdowns are worth six points and field goals are worth three points.