The gaseous state is one of the four fundamental states of matter, alongside solids, liquids, and plasmas. In this state, particles are far apart and move freely, allowing gases to fill any container they occupy. This means that gases have no fixed shape or volume, making them highly compressible. Common examples of gases include oxygen, carbon dioxide, and nitrogen. Gases behave differently than solids and liquids due to their unique properties. For instance, they can expand to fill larger spaces and can be easily mixed with other gases. The behavior of gases is often described by gas laws, which help explain how temperature, pressure, and volume are related.