Though it's not always necessary or even desirable to establish friendships with your colleagues, you should aim to build solid working relationships with them. And while it pays to get along well with everyone at the office, there are certain coworkers who are worthy of some added effort. Here are a few to focus on.

1. The go-getter

If you work in a fairly large office, you've probably come across at least one coworker who just seems more driven and ambitious than others. This is a person you'll want to establish a relationship with for a couple of reasons. First, if that colleague manages to work their way up, you'll have someone at the top in your corner. Secondly, there's a good chance you'll be able to learn a thing or two from this person, whether it's a hard skill specifically related to your job or a soft skill that's just as valuable.

Professional man and woman walking and talking in an office.

IMAGE SOURCE: GETTY IMAGES.

2. The lifer

Many established companies have at least one employee who's a lifer -- in other words, that person started out in his early 20s and plans to stay put until they're ready to retire. Learning how to work well with a lifer will benefit you because this person knows the ins and outs of not just the company, but the players involved. You might pick up pointers on who to impress if you're vying for a promotion or whose bad side not to get on.

3. The unsung administrative hero

Maybe you're extremely adept at writing marketing copy or developing code for your company's proprietary software. Critical as those skills might be to your particular role, there's a good chance you wouldn't be able to do what you do if it weren't for someone behind the scenes keeping the office running. If your company has a superstar admin who knows how to fix the temperamental copier, troubleshoot internet outages, and perfectly stock the snack cabinet, that's a person you'll want to know.

Having a good relationship with an awesome administrative person could help you in a number of ways, whether it's calling dibs on a conference room or snagging a better office the next time one becomes available. Just as importantly, that admin might let you in on their secrets, and once that happens, you'll get a chance to be the resident hero, too.

4. The grammar whiz

Though being good with grammar isn't always essential to succeeding in the business world, it often helps. That's why it pays to build a relationship with your in-house grammar guru -- you know, that person who's constantly reminding people to use "whom" rather than "who." The grammar whiz might be constantly nit-picking, but they're the perfect person whose help to enlist when you have a major report to submit or a presentation to make before upper management, so gain that coworker's support and pay attention to their tips.

5. The optimist

It's hard to have a positive attitude when deadlines are looming and your workload keeps piling up. But if you have a colleague who tends to approach challenges with gusto rather than disdain, you'd be smart to get to know them a bit better. Not only might their optimistic outlook rub off on you, but you might gain some insight as to why they're always so chipper.

Is it because they've mastered the art of staying organized? Are they great at project management? Find out their secrets and employ them yourself, and with any luck, you'll learn to stay cool in the face of pressure.

The harder you work at building strong relationships with your coworkers, the more you stand to gain in the long run. Focus on the right ones, in particular, and you'll be setting the stage for your own personal success.