This photo is from season one, episode two ("Purple Giraffe"), which aired in September 2005, the year we're first introduced to Barney, Robin, Ted, Marshall and Lily. Cheers!

Season two gave us our first glimpse at Robin Sparkles, the teen alter ego of Robin. This CSI spoof photo from 2007 is for a March Madness promotion.

Barney and Marshall's slap bet continues in season three's "Slapsgiving" episode from 2007.

Lily competes in a wild hot dog-eating competition in "The Stinsons" episode in 2009.

The gang performs a musical number during "Girls Versus Suits," which marked the show's 100th episode in 2010.

The fivesome travels to Minnesota for the funeral of Marshall's dad during the "Last Words" episode in 2011.

Everyone congratulates Marshall after Lily gives birth to their baby in "The Magician's Code Part One" in 2012.

After several rocky years, Barney finally asks Robin for her hand in marriage during two-part "The Final Page" episodes in 2012.

Always one for surprises, Barney orchestrates a Canadian-themed wedding rehearsal dinner party for Robin during the "Rehearsal Dinner" episode in 2013.

Ted will finish telling his kids how he met their mother during the March 31 series finale.

Self-fives might be a little conspicuous around the office, but there's nothing wrong with taking pride in your accomplishments, even if they're as simple as getting the printer un-jammed.

Offer to take on a responsibility outside your job description, and raise your hand when your boss asks for volunteers. As Barney has proven, even if it doesn't go as you hoped you'll learn a lot about yourself and your abilities.

Unless they're Patrice. It's ok to ignore Patrice.

A Wikipedia page on successful people who followed the rules 100 percent of the time would be really short.

Sometimes it's impossible to tell if your co-worker is actually crazy or you've just sat in the next cubicle for too long. Talk it out with a friend who's not afraid to tell you if they think you're the problem.

That includes learning the proper pronunciation of everyone's name who might show up for a meeting, as well as how to work the computer you'll be using for your presentation. You never know when you might be called on.

When Ted gets in a funk about his future, no progress is made and no fun is had. Allow yourself fifteen minutes to vent, then make some goals, possibly while listening to 'Eye of the Tiger.'

Even if your Facebook is private. Even if your boss doesn't even know what Twitter is. It's always safest to avoid complaining online about your job.

Throwing on a suit (or dress) can make everything seem better. (Or at least more professional.)

Everyone has their own set of strengths. Sometimes the smartest thing you can do is recognize that a co-worker's strength compliments your weakness, and agree to help each other.

How many times did one of the HIMYM five end up job-less, pants-less, on the couch eating ice cream? Once you see it as a temporary setback instead of an indication of the direction your life is heading you can just enjoy your mid-morning sundae.

Nothing will escalate a problem faster than bringing it to the higher-ups before your co-worker knows about the issue. It's always an awkward conversation, but it's better than having to deal with their death stare after the fact.

Accept compliments and don't be afraid to rattle off your qualifications when you want more responsibilities. Just make sure you let your co-workers have their moments too.

Listen during the meetings, no matter how much you want to play Candy Crush under the desk. Listen when your co-worker is talking, even if you think it doesn't concern you. Listen when the guy from IT is telling you about his daughter's play. The more you know, the more capable and valuable you'll be.

Sure being the lottery numbers girl is easier, but an entry-level journalism job is more rewarding. Always work toward your dream job.