Four Cover Letter Mistakes That Could Prevent You From Getting an Interview:

People freak out about cover letters, as if one line will make or break their chance of getting a job. But they're really just a formality, and you'd have to have make blatant spelling and grammar mistakes for you cover letter to be a dealbreaker. But in this economy, why take chances: Here are four other things that can actually ruin a good cover letter.

#1.) Don't Make It Too Short or Too Long. According to the president of one staffing firm in New York, it should be somewhere between 200 and 250 words. If it's shorter, you'll look like you didn't try. And if it's longer, they might just skip it. He also says you should highlight one major accomplishment, like saying you increased sales by 50% in a year. He says that if he reads something concrete like that, he'll look at the resume.

#2.) Personal Stories. The major accomplishment you highlight HAS to be work-related. So if you're applying for a job in communications, don't talk about how you ran a half-marathon last year. They won't care. Instead, save it for the interview, so you'll have a good answer if they ask what your hobbies are.

#3.) Don't Criticize the Company You're Applying To. It sounds obvious, but some people submit cover letters with lines like, "Your company looks great. But from your website, I can tell you need help with marketing." You might think it'll make you stand out as someone who can immediately bring something to the company. But in reality, it just makes you look arrogant.

#4.) Jokes. If the person reading it doesn't know you and you don't know their sense of humor chances are the joke won't land. But even if it does, you'll look unprofessional. Jokes are even risky during an interview, because the best-case scenario is, they'll think you're funny which probably won't get you the job. And the worst-case scenario is, they'll think you're an IDIOT which DEFINITELY won't get you the job.