1. Don't make Luis Suarez mad.
Who knows what the Uruguay striker will do -- or bite.
Suarez was banned from the World Cup after he chomped on opponent Giorgio Chiellini's shoulder during a match against Italy in Brazil on June 24.
The bizarre bite prompted memes like #suarezing and reminded fans why Suarez is nicknamed "The Cannibal."
2. How to cheer like real football fans.
The chant "I believe that we will win" should be burned in all of our brains by now.
The U.S. showed their support in a big way this year, with superfans like the American Outlaws flying around Brazil to follow our national team from match to match.
Their fervor for the sport is catching on -- Americans bought more tickets for the 2014 World Cup than any other nation except Brazil, FIFA said.
3. Everyone loves Tim Howard.
And who can blame them? The U.S. star goalie broke a World Cup record when he made 16 saves during a July 1 match against Belgium.
It wasn't enough for a win, but fans were still amazed by Howard's impressive play, naming him the U.S. Secretary of Defense in a cheeky Wikipedia entry, and earning him and captain Clint Dempsey a phone call from President Obama.
4. Everyone loves to hate Cristiano Ronaldo.
From his perfect hair to his supermodel girlfriend, it's easy to resent Portugal's star Cristiano Ronaldo.
But the U.S. actually has him to thank for advancing to the round of 16.
Ronaldo scored a goal in the 95th minute of a Portugal-Ghana match on June 26, which kept Ghana from knocking the U.S. out of the tournament.
Fans even jokingly called Ronaldo an "honorary American citizen."
5. Some people really, really hate FIFA.
It was hard to ignore the protests and "FIFA Go Home" signs that cast a dark cloud on the tournament in Brazil. For many viewers, it was the first time they learned of the corruption allegations that plague the soccer association.
Billions of dollars were spent building stadiums and preparing the country for an influx of tourism, cash that should have been spent on bettering public services in Brazil, critics said.
FIFA is also in hot water over allegations that Qatar bought influence for its 2022 World Cup bid.
6. Everyone needs to visit Rio.
Sure, Brazil lost the World Cup on their own turf, but it's hard to feel bad for anyone who can drown their sorrows with a caipirinha in Ipanema.
Soccer might have been the real attraction, but those gorgeous beaches in the background were a close second. Watching fans cheer on the white sand with the bright blue sea in the background made us all want to book a flight to Brazil.
7. Losing hurts.
On that note, no one likes to lose. And it can even affect your health, research shows.