Thanks to the common cold, basically no one likes mucus. Even the word itself is enough to make some people queasy, but science tells us mucus is getting a bum wrap. Mucus is our friend, even when you have a runny nose. Proteins in your mucus called mucins create a barrier against pathogens that might seek to infect your body. What else does mucus do? Check out this video from TED-Ed to find out, and maybe say a little thank you next time you throw away a tissue. Your mucus is hard at work keeping you healthy every day.