by Meg Jones
"Friends With Benefits" hits theaters Friday, and we simply can't wait to see Justin Timberlake and Mila Kunis' on-screen chemistry (and those much-talked about butt shots of JT!). As part of the romantic comedy's ad campaign, the two stars have asked everyone to donate their FWB status via Facebook (watch the clip below!). But what exactly does such a relationship entail? We'll have to watch the movie to see Justin and Mila's take on it, but we do know that the duo swear over an iPad app of the Bible that it will be "no emotions, just sex."
Anyway, all this FWB talk got us thinking about other relationship acronyms and the celebrity couples who fit them LAG (like a glove, obvi). Keep reading after the jump for our run-down of the most important three-letter shorthands in Hollywood.
PDA—Public Display of Affection
There is no question as to whether Justin Bieber and Selena Gomez are into each other. It was all hand-holding and sly glances until the couple took PDA to a whole new level at the Billboard Music Awards when they locked lips on camera in front of millions. This young love is no longer a secret, as they have been snapped canoodling on vacation in Hawaii, giving each other foot massages and even crashing weddings! Doing some matrimony research, guys?!
DTR—Define the Relationship
Kristen Stewart and Robert Pattinson—are they or aren’t they? These two continue to be our favorite non-couple couple. We can’t wait for Bella and Edward’s wedding in "Breaking Dawn," but will we ever see the real KStew and RPattz walk down the aisle? For now, we can only hope.
LDR—Long Distance Relationship
The LDR is not easy to pull off, but leave it to Kim Kardashian to do it and do it well. It’s no secret that Kim K. has been itching to get married, and it looks like her bi-coastal engagement with beau Kris Humphries is working out so far. Between her hectic schedule of photo shoots, appearances and filming "Keeping Up With The Kardashians," Kim always seems to find time to travel around the country to be with her New Jersey Net (and cheer for him on the sideline of the b-ball court). We're just counting down the days until their televised nuptials. (You know it's going to happen...)
RR—Ring Ready
Brangelina…enough said. Brad Pitt and Angelina Jolie marriage rumors spread like wild fire but are always quickly put out. This celebrity power couple's romance bloomed while filming the 2005 action comedy "Mr. and Mrs. Smith," and they certainly played the part of husband and wife well (talk about on-screen chemistry!). Now, six years and six kids later, we’re all left wondering, where’s the ring? They've said publicly that they won't tie the knot until marriage rights are universal, and with New York approving same-sex marriage recently, it looks like the path's becoming a bit more clear.
MWK—Married With Kids
Originally dubbed Posh and Becks, soccer star David Beckham and Spice Girl Victoria Adams married in 1999. At that point they already had a son, Brooklyn, and since then they have added two more boys, Romeo and Cruz. The Beckhams and their brood of boys just welcomed daughter and sister, Harper Seven, into the family last week. The boys even helped name their new baby sister—after Harper Finkle, a character in their favorite Disney show, "Wizards of Waverly Place." Adorbs! We love this beautiful family and can’t keep our eyes off hubby David. Victoria, you are one lucky lady and mom!
Any relationship acronyms we missed? Which couple on our list is your favorite? Will you be seeing "Friends With Benefits" this weekend? Sound-off in the comments and on Twitter!

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