The Super Bowl has become part of American culture, and is sure to draw a huge TV audience

Super Bowl Sunday is the biggest day in American sports; it long ago evolved from a sports spectacle into a social event that spans all ages, genders and backgrounds.

A winery in California has invited oenophiles to an anti-Super Bowl party. Acquaintances in New York City have organised an anti-Super Bowl group dinner at an Italian restaurant. A theatre in California is presenting an anti-Super Bowl comedy party with professional comics.

In the United States, escaping the ubiquitous showing of the Super Bowl is so challenging that those disinclined to watch The Biggest Game Of All must unite like revolutionaries while doing their anti-establishment thing.

Super Bowl Sunday has evolved into the nation's newest national holiday, focused for most Americans around a flat-screen television.

Last year's game – the XLIVth, for those counting, in the NFL-preferred Roman numerals – drew 106.5 million viewers, making it the most-watched TV programme in the nation's history. The number surely will be topped today; both teams have national fan bases, many Americans are housebound by snow and the league has enjoyed through-the-roof television ratings all season.

The Super Bowl TV audience might actually be underestimated because the ratings system does not fully account for large gatherings. Game-viewing has become a significant 21st century social event for Americans, joining New Year's Eve and Halloween as the most party-filled on the calendar.

.No one watches TV advertisements anymore. Except, of course, during the Super Bowl, where advertisers pay up to US$2.8 million (Dh10.3m) for a 30-second spot.

Sponsors hire famous directors to create the ads. The day after, those not buzzing about the game are grading the high-priced clips between plays.

When half-time arrives, do not switch to another channel as you would for any other game. The Super Bowl half-time show has become a happening within a happening.

From the early days of college marching bands, the NFL set the entertainment bar sky-high in 1993 with a mini-concert by Michael Jackson. Since, the parade of entertainers seems to have poured straight from the Rock and Roll Hall of Fame: U2, Paul McCartney, the Rolling Stones, Prince, Bruce Springsteen, The Who.

The notorious "wardrobe malfunction" during the performance by Michael's kid sister, Janet, triggered a legal tussle between TV networks and the Federal Communications Commission over censorship. The FCC fined CBS in a case that remains legally unsettled, which reflects how deeply the Super Bowl is embedded in the American culture.

Need a table at your favourite overcrowded restaurant? On Super Bowl night, take your pick. Eager to check out an Oscar-nominated movie at the cinema? Spread out over several seats, if you like.

The Monday after generates one of the highest workplace absentee rates of the year. At least one employer, US Steel in the Pittsburgh area, warned that workers who skip their shift during or after the game will face "severe disciplinary action".

And if you hold that anti-Super Bowl party, be prepared for what one host encountered last year, as detailed on a blog: "There is a pot of cold chilli on the counter and chips, guacamole, and drinks. Not a single person has shown up."

KEY BATTLES

Green Bay offence v Pittsburgh defence
The Packers cannot count on moving the ball on the ground against the league's best run-stoppers, but they must get something out of James Sparks. It will not be easy with Pittsburgh's Casey Hampton clogging the middle. Aaron Rodgers, the quarterback, must be sharp again. Because his mobility can buy him time to find receivers, Rodgers, pictured below, makes the unimpressive Steelers cornerbacks vulnerable, so safeties Troy Polamalu and Ryan Clark will look to make big plays. The Steelers are blitz-crazy; Green Bay might have to keep an extra blocker in the backfield. Expect the big-hitting (and oft-fined) linebacker James Harrison to try to shake up Rodgers.
Key stat: Rodgers has thrown 25 touchdowns and five interceptions in 11 career games indoors. His 12th is today.

Pittsburgh offence v Green Bay defence
He is known as Big Ben, but the quarterback Ben Roethlisberger could be nicknamed Big-Play Ben. The speedy receivers Mike Wallace, Emmanuel Sanders and Antonio Brown allow him to throw the ball deep on timing patterns as a counterbalance to short-yardage receiver Hines Ward. The rushing game is all Rashard Mendenhall.
Key stat: The Pittsburgh receivers averaged 13.1 yards per catch, second in the league only to San Diego.

Special teams
Both teams have solid kicking games and are unlikely to break a big return.