The common cold is a mild viral infection that affects your nose and throat, causing sniffles, sneezes, a scratchy throat, and sometimes a cough. It's called “common” because people catch colds so frequently: most kids get several colds each year, and adults typically get two or three. You've almost certainly had one.

Colds spread easily when someone who's sick coughs or sneezes, releasing tiny droplets containing the virus into the air. You can also catch a cold by touching a surface an infected person touched, then touching your own nose or mouth. That's why washing your hands regularly helps prevent colds.

While colds can make you feel miserable for several days, they're rarely serious. Your body fights off the virus on its own, usually within a week or so. There's no cure for the common cold (antibiotics don't work on viruses), but rest, fluids, and time will get you better. Scientists have tried for decades to develop a cold vaccine, but the challenge is enormous: over 200 different viruses can cause colds, and they keep changing.

The phrase “it's not rocket science” is sometimes paired with “it's not curing the common cold, either,” acknowledging that some seemingly simple problems turn out to be remarkably difficult to solve.