Last week, the White House fired an aide who was accused of “trolling” Washington officials.

Jofi Joseph, who used the alias @natsecwonk, used his Twitter account to lash out at politicians and staffers he disagreed with. When he was found out, he found himself out of a job, according to an NPR story.

Joseph’s is not an isolated incident. Who can forget June’s Taco Bell incident, in which an employee was pictured licking a stack of taco shells. CNBC reports he was fired soon after the incident, although Taco Bell maintains the shells were never meant to be sold.

Articles on CNN, the Wall Street Journal and even satire site Cracked.com all show examples of people who were fired for reckless social media behavior, from taking pictures of themselves engaged in illegal activities, to criticizing their places of work or just behaving in an uncivilized manner.

A report on Indiana-based news station WNDU shows that not even putting your messages or statuses on “private” or “friends-only” can do much to help. Anyone on your “friends” list need only take a screenshot or save an image, and the content becomes out of your control.

It doesn’t matter if you’re a low-level employee or the chief financial officer of a company. If you put forth the wrong social media presence, you can find yourself fired — if you can even get the job in the first place.

That’s right. It’s not just the job you have that you need to worry about. It’s also the job you want.

Rachel Ryan, a blogger for the Huffington Post, wrote that her “jaw hit the floor” upon finding her boss scouring the social media profiles of job applicants.

Even more frightening is that some employers need only 10 minutes on your Facebook profile to create an impression of a job candidate, according to Forbes. A cursory evaluation of statuses, photographs and topics can give an employer a rough estimate of your personality and potential work performance.

Starting to think about those photographs of you holding a red cup at a certain party last year? Wondering if maybe there’s one expletive too many in your history?

Websites like About.com have lists of dos and don’ts for social media, especially when looking for a job. Just like you may fervently clean your living space when your parents are coming for a visit, you need to scour your social media presence when looking for a job.

The Huffington Post has compiled a list of six things employers don’t want to see on your Facebook, including drug use, provocative photos, badmouthing previous employers and “poor communication skills.”

Yes. That means they’re parsing your grammar and syntax as well, so you need to watch your language in more ways than one.

Even if your qualifications are in order, frequent misspellings and “text-speak” are both job repellents. Most post-college jobs will eventually involve some level of written communication, and HR people like the idea of hiring people whose writing they can decipher.

Think before you post. Think about what sort of a person your online self is, and if that’s the sort of person you’d hire.

If you think your online self isn’t a good reflection of your actual self, maybe it’s time for a makeover.

Your friends might have hit the “like” button on your party pictures, but that won’t mean much when a screener hits the “delete” button on your application.