Work friends are, if not essential to survival in the office, at least essential to enjoying the office. That being said, all offices have the same types of friends. Every workplace has a know-it-all, for instance. And no matter where you work, there's always going to be someone who seems to have the freshest gossip. Here's a field guide to the species you are likely to encounter.

The Office Couple: Every office has at least one of these: that slightly dysfunctional, nonromantic pair who plot their office dominance together. Their ambition is obvious; they finish each other's sentences, and their slightly intense bond tends to creep out everyone else.

Also known as: Secret Frenemies

The Fashion Crush: This person is the rare colleague who knows exactly how to dress for all occasions and frustratingly seems to pull off every new trend effortlessly.

Also known as: The Cool Girl (or Guy)

The Pharmacy: This co-worker always knows just how to fix whatever ails you. Popular wares include (but are not limited to) Band-Aids, pain reliever, contact lens solution, safety pins and, if you're lucky, a flask. Do not abuse this valuable resource; no one wants the Pharmacy to close up shop.

Also known as: Office Parent

The Work Crush: This person has always been a workplace staple, but the advent of internet dating means that you embarrassingly come across this person's Tinder profile during innocent swiping sessions.

Also known as: The Office Dreamboat

The Carb Pusher: Your weekly renewed commitment to eating better is destroyed by this well-meaning person. Homemade cookies? Check. Bagel Fridays? Of course. Your willpower? Gone.

Also known as: The "Who Wants to Order Pizza?" Guy

The Work Ghost: This distinction goes to those people who have mastered the dark art of staying employed without ever seeming to actually make it into the office.

Also known as: Your Boss

The Workout Buddy: This is the colleague who will try to drag you to every barre, yoga, rowing and kickboxing class in the immediate area. This kind of person enjoys comparing fitness tracker statistics with strangers.

Also known as: The Corporate Discount Procurer

The Meat Shield: This term has murky origins; it's popular in the video game world and is referred to in "Survivor." And it perfectly suits the colleague who tends to enjoy meddling in office battles, unwittingly taking the heat off other colleagues.

Also known as: The Reply-All Fanatic