Last week, the cybersecurity company CrowdStrike pushed a software update that brought the United States, and much of the world to a halt. The faulty update grounded planes, strangled businesses, and even took out a Formula 1 team. Even today, the company's stock continues to fall as the world comes to terms with just how beholden it is to a few programs. In short, someone really really messed up at work. 

Taking to AskReddit, these 21 people decided to share the times they royally screwed up on the job, and whether or not it cost them their heads. Granted, nobody here messed up on a "bring the world grinding to a halt" scale, but quite a few of these people were lucky to escape with their jobs and without a lawsuit. 

Here are 21 employees sharing their biggest work screwups.