You may know little about your colleagues other than what their jobs are. An office party gives you a chance to become acquainted with them on a whole other level. Getting to see them in a different environment may make you look at them differently. Ignore your animal instincts. 

Workplace romances—or worse, one night stands—can be disastrous.

Know your limits and don't go beyond them. One alcoholic beverage—or even two if you are sure you can handle it—is OK. Although you may know a third drink won't be a problem for you, keep in mind that perception is everything. You want to avoid looking like you are drinking too much.

Don't think about flirting with coworkers, even if it's entirely innocent.  Flirting or acting in a sexually provocative manner can, at best, make colleagues lose respect for you on a professional level. At worst it can end with a claim of sexual harassment against you.

Your boss is watching. Your coworkers are too. Don't show a side of yourself that could be embarrassing or cause their opinion of you to change for the worse.  For example, don't share too much personal information if you wouldn't want it to be known in a professional setting.

Feel free to tell jokes, as long as you are sure they won't offend your coworkers or boss (or worse, his or her boss).  Many people do not enjoy off-color jokes, so refrain from telling any. On a related note, you should also be wary of using foul language. 

Employers throw parties to reward their workers and give them time to socialize with each other.  How can you take advantage of this opportunity if you are constantly checking your phone? Put it away and try to focus on the here and now.

When your boss throws an office party, he or she may intend it to be for employees only. Never assume it's OK to bring your significant other or anyone else without asking first. Showing up at an event with a plus-one may anger your boss and embarrass your guest if he or she feels unwanted.

Whether on the job or at a work-related event, it is in poor taste to gossip.  You may run out of things to discuss with your colleagues so you decide to fill the silence by talking about those people who couldn't attend the festivities. If the fact that it's just not a nice thing to do doesn't 

deter you, think about how you will feel if word gets back to him or her.