The NFL teams have finished the season with eighteen wins and one loss:
49ers
N E patriots
The 2007 New England Patriots were the only team to be at 18-0 at one point during an NFL season. The Patriots were 16-0 during the regular season, then won 2 post season games. They would then lose in Super Bowl XLII to the New York Giants and finish their season at 18-1. The 1972 Miami Dolphins were the only team to go undefeated the entire season. The Dolphins were 14-0 in the regular season and then won 3 post season games, which included the Super Bowl, to end the year at 17-0.
2007 Patriots, 1985 Bears, 1984 49ers
Orioles and Yankees
Adrian Peterson lead the NFL in 2009 with 18 touchdowns.
18 - 85 Bears
They are currently on an 18 regular season game winning streak, dating back to the 2008-09 season where they finished with 9 straight wins.The Colts are currently 9-0 in the 2009-10 season and are tied for 2nd with the longest regular season winning streak with the patriots
As far as we know there's only seven seasons and they just finished season 3 which wasn't on the island and neither was season 2 so there's no season 18
17-0 Miami Dolphins 18-0 Patriots
In the 1980 NHL season, each of the 21 teams played 80 games.
The 2007 New England Patriots had a 16-0 regular season, and two playoff wins to post an 18-1 record (lost Super Bowl), Two other teams had 15-1 records and won three playoff games: 1984 San Francisco 49ers 18-1 1985 Chicago Bears 18-1
Yes. Each season teams will play 15 to 18 games against teams from the other league.