The success of "The Social Network" at the box office this past weekend has many mid-20-somethings nostalgically reminiscing back to the days of "The Facebook" (circa 2004), long before the advent of so-called "privacy settings." It was a carefree time when users needed a .edu e-mail address from a select network of schools and college students openly posted party pics without any sort of inclination that their drunken photos would seen by a prospective employer or, maybe worse, a curious aunt or parent. Six years, hundreds of millions of users, and billions of theoretical dollars later, Mark Zuckerberg's online Frankenstein continues to be the most culturally relevant social network on the Internet.

It also continues to be the ultimate online depository for women to upload photos of themselves. In turn, every warm-blooded man with a pulse and an Internet connection has squandered countless hours gawking at pictures of hot female friends — and friends of friends — on Facebook. After hours of our own thorough analysis, we've compiled the 15 most common photo tricks girls use to heighten their sex appeal and inflate their looks in their Facebook photos. Check them out after the jump.

15. Posing for Group Photos with the Infamous "Angled-Knee Trick"

Facebook must have entire servers dedicated to storing photos that are a mirror image of the example above. When a group of girls huddle up to take a photo, the posture is almost universally the same: shoulders back, one knee slightly bent, and a foot forward at an angle. Points on the hotness scale skyrocket for showing some skin.

14. Posing for Group Photos with the Infamous "Strong-Arm Trick"

The so-called "Strong-Arm Trick" is pretty much a bastard cousin of the knee-out trick, as demonstrated above in the lake vacation photos of Oregon's Cheerleading squad. It's traditionally an optical illusion for tough girls (think rowers and field hockey players) to lose camera pounds in their arms. The basic protocol is a three-step process. First, the girl angles her body toward the camera. Second, she places her hands on her hip. Third, she pushes her funny bone back toward their shoulder so either (a) the muscle doesn't bulge out or (b) flab on the front and back of her arm doesn't jiggle when the photographer snaps the picture.

13. The Bend-Over Trick

Chicks love to show off how well they can do the ChaCha slide on Facebook by posing for pictures with their hands on their knees and their asses extended in full grind position. This is also a precursor to common way #9, below.

12.  The Bend-Over, Squeeze-the-Chest Trick

Yes ladies, we're staring at your ones-and-twos. Unlike the traditional bend-over pose, the purpose of this classic Facebook photo is to highlight the subject's glorious rack, thus taking the attention off of the girl's face. It's a blissful optical illusion for a butterface, and especially effective when the b**bs are squeezed together.

11. The Girl-on-Girl Hug Trick

It's a common pose for girls who wish to show their warm affection for each other.