Aspirin is an non-steroidal anti-inflammatory drugs and over-the-counter analgesic. Non-steroidal anti-inflammatory drugs are drugs that reduce pain, decrease fever, decrease inflammation... Aspirin is used in conditions like common cold, headaches, muscle aches, toothaches, ... Over-the-counter analgesic are drugs that you can buy from a pharmacy or shop, without needing a prescription from your doctor. Aspirin is one of them.