In the 21st century, most of the NFL regular season was played under a 17-week format that offered fans 16 games, that was until 2020, the year of the covid-19. But during the current 2021-22 regular season one more week was introduced for a total of 18 weeks.
The first time it was played under an 18 weeks format was in 1993 when an additional bye week was included. During that season the winner of the Super Bowl was the Dallas Cowboys, that was the team's third super bowl in the 90s.
Week 18 is a good opportunity for some teams that depend on one more victory to reach the playoffs and other teams that depend on one loss. More games will open more spots to weaker teams during the second half of the regular season.
What is the reason behind 18 week schedule in the 2021-22 NFL regular season?
Week 18 entered the NFL again due to a new collective bargaining agreement that they signed a season earlier, thinking of making cuts in the preseason and adding one more game for the regular season. The NFL went from 16 games to 17 games so it was necessary to include an extra week.
It is very likely that the season will continue to be 17 games in the upcomin years which translates to 18 weeks, otherwise it would be adding too much game load to the teams and players since some games would have to be played Tuesday or Wednesday.