Ethyl mercaptan is a colorless gas with a strong, unpleasant odor, often described as similar to rotten eggs or garlic. It is primarily used as an odorant for natural gas, which is otherwise odorless, to help detect leaks. This compound is a type of mercaptan, which contains sulfur and is known for its distinctive smell. Ethyl mercaptan is also used in the production of various chemicals and as a flavoring agent in some food products. Its strong odor makes it an effective warning signal in safety applications.