Pam is the cute as a button receptionist who is probably best known for her
3 year engagement to Roy, the short tempered warehouse worker. However, the
whole time she was engaged to Roy, she was secretly in love with Jim. Eventually,
she broke up with Roy and cancelled 
her wedding, saying "she needed to get out of
that relationship." However, at the time, Jim was in a relationship with Karen from the
Stanford branch, and so, Pam gravitated back to Roy.
Pam eventually told Roy that Jim kissed her, and his subsequent violent reaction (he basically singlehandedly trashed Poor Richards, the local watering hole) made her ditch him again. Roy then tried to beat up Jim, which resulted in his termination and the straining of Pam's relationships with Jim and Karen. Jim and Pam eventually got together in Season 5, and that's where things stand now.
Pam is the victim of a lot of sexual harassment; Michael has called a cuter girl "Pam 2.0",
and Kevin called Pam's mom a "M.I.L.F." She also sees herself as less respected than
other members of the Dunder Mifflin staff, and on a staff outing one day, she completed a challenge
that no one (save Dwight) was able to do: walk over a 
bed of fiery coals. Her subsequent
adrenaline rush caused her to blurt out some embarassing personal confessions,
including her missing Jim as a friend and her resentment of everyone treating her as if
she was persona non grata.
Pam is an artist, and has won a few contests for her water color works. She recently went to school in New York, and with the help of a tiny, Japanese bluetooth ear piece, she was able to stay in touch with Jim 8 hours a day. Although one of Pam's co-workers tried to persuade her to stay in New York, she realized that she hated graphic designed and loved Jim, so a-home she came.