NFL 2015: Can Odell Beckham Junior do it again?

Do you know your quarterbacks from your Cheeseheads? Your Odell Beckham from your David Beckham? Did you think deflate-gate was about a flat tyre?

Don't worry, all you need is our guide to the new American football season, which starts on Friday (01:30 BST) when defending champions the New England Patriots face the Pittsburgh Steelers in Boston.

All 32 NFL teams will be in action across the weekend hoping to reach the landmark 50th Super Bowl in Santa Clara, California, on 7 February.

But what is it all about? How can you impress your American friends? Can you bluff your way through the league's best teams and players? Here's all you need to know…

Who could win the Super Bowl?

Last year's Super Bowl had a spectacular ending as the Patriots fought back in the final quarter against the much-fancied Seattle Seahawks to win 28-24. Most bookmakers and pundits are tipping both teams to go far again this year - and it is hard to argue against that.

Seattle Seahawks' Russell Wilson, Green Bay Packers' Clay Matthews and New England Patriots' Rob Gronkowski

Richard Sherman, famous for his hard-hitting tackles and quick-fire trash talk, leads Seattle's 'Legion of Boom' defence, the best in the league. And with quarterback Russell Wilson at the helm, the Seahawks will be looking for their third Super Bowl appearance in a row.

New England quarterback Tom Brady will be hoping to put deflate-gate behind him and, together with powerful tight end Rob Gronkowski, is looking for the Patriots' fifth Super Bowl title since 2001. They are coached by Bill Belichick, the only head coach in history to have won three world titles in a four-year span.

Others to keep an eye on include quarterback Aaron Rodgers and his Green Bay Packers, the Andrew Luck-led Indianapolis Colts and Peyton Manning's Denver Broncos.

Teams less fancied include the Jacksonville Jaguars, who will be facing off against the Buffalo Bills at Wembley on 25 October, the Oakland Raiders and the Tennessee Titans.

What was deflate-gate all about?

Roger Goodell, NFL commissioner since 2006, went to court with Tom Brady when the latter's suspension was overturned

New England's hopes have been boosted in part by the return of star quarterback Brady, who is now eligible to play from the first week of the season following a turbulent off-season.

A hospital announcement and an array of memes are among the way NFL fans reacted to a judge overturning a four-game suspension for quarterback Tom Brady

Brady had been suspended for four games by the league after it was found balls used by him in the game which took the Patriots to the Super Bowl had been under-inflated.

The Patriots easily won the American Football Conference game 45-7 against the Indianapolis Colts, but that did not stop a very public and damaging investigation into the affair by the league and its boss, commissioner Roger Goodell.

Brady, backed by Patriots owner Robert Kraft, protested his innocence but the NFL went ahead with a suspension and fined the Patriots a record £660,000. However, earlier in September, a US judge overturned the suspension, claiming the case had "legal deficiencies", meaning Brady can now take part in the season's opening game.

The NFL has said it will appeal so the saga may continue.

Who are the best players this year?

NFL's best defensive plays of 2014

Tricky question but there is certainly plenty of talent about. Not least defensive end JJ Watt of the Houston Texans, who recently showed off his huge frame while stood next to another sporting superstar - Barcelona's Lionel Messi.

A regular winner of defensive player of the year awards, the Wisconsin-born defensive end weighs in at about 289 lb (131 kg) and stands at 6ft 5ins tall (1.96m). He has been recently starring in US reality documentary series Hard Knocks about the Texans, where he showed off his strength lifting 1,000-pound tyres (454 kg) and explained how he once lifted 65 in one day.

Watt also eats 9,000 calories per day - the equivalent of 25 cheeseburgers.

NFL: Best of the running backs 2014

Other big players who will be hard to miss include New York Giants wide receiver Odell Beckham Jr, who caught a stunning one-handed catch last season, and Green Bay Packers quarterback Aaron Rodgers, who was named the league's Most Valuable Player last season. Minnesota Vikings running back Adrian Peterson also returns to action following a ban for "recklessly assaulting" his son.

Former Australian international rugby league player-turned NFL running back Jarryd Hayne could also be one to follow after his move from Australia's National Rugby League to the San Francisco 49ers, having impressed in pre-season.

Former British Olympic discus thrower Lawrence Okoye, 23, will be flying the flag for Britain as a defensive end for the Arizona Cardinals, with fellow countryman Jack Crawford also making the Dallas Cowboys' roster.

Manchester-born Oakland Raiders player Menelik Watson, 26, is likely to be out injured for the year, as is Londoner Jay Ajayi of the Miami Dolphins.

Which team has the best fans?

There are some recognisable fan bases across the NFL - but the 'Cheeseheads' of the Green Bay Packers top the list.

Based in the "dairy state" of Wisconsin and known for braving sub-zero degree temperatures, Packer fans were ranked as the league's best supporters by Forbes magazine last year after taking into account home-town crowds, TV audiences, stadium attendances, social media numbers and merchandise sales.

Oakland Raiders' fans and a Green Bay Packers 'cheesehead'

Green Bay, who have won the most league championships in history (13), boast more than four in five adults in their city as fans.

The franchise operates in the league's smallest market with a city area population of just above 300,000, but has more than a million Twitter followers and almost five million 'likes' on Facebook. The Packers also have one of the longest season ticket waiting lists in the league and One Direction's Harry Styles is also a fan.

Taking into account Twitter followers, look no further than the New England Patriots (1.45m) and the Dallas Cowboys (1.37m), often dubbed "America's team". However, for enthusiasm and costumes, the Oakland Raiders fans often top the charts.

Who to follow on social media…

The battle for followers and likes can be as competitive as the action on the field in the world of the NFL.

The NFL's official account is an obvious point to start, boasting almost 13 million Twitter followers and more than 12.3 million Facebook likes. However, this week the account gained criticism for tweeting about possible Super Bowl contenders and missing out Tom Brady. The post was later deleted.

Quarterback Tim Tebow gives his insight on ESPN America

Other accounts to be across include ESPN's Adam Schefter, who has more than three million followers. Seattle's Richard Sherman has been known to entertain with his musings while Matthew Berry's insight into the world of fantasy football has gained a following. Former NFL quarterback Tim Tebow also has a wave of fans.

What else should I know for this season?

NFL: How the New England Patriots won Super Bowl 49

The NFL is back on the BBC as part of a new two-year deal, which includes coverage of Super Bowl 50 on TV, radio and online.

If you really want to impress your American friends, don't forget to mention Sarah Thomas, who will become the league's first full-time female game official.

The extra point kicked after touchdowns will be moved back to the 15-yard line for the first time to make them a little harder, and this season will be the first year where the Super Bowl will not use Roman numerals, with the league opting for Super Bowl 50.

In the first week of the 17-week season, rivals such as the Dallas Cowboys and the New York Giants will compete, the Chicago Bears and the Green Bay Packers are also matched up and the Philadelphia Eagles face Atlanta Falcons.