Aerospike nozzles are a type of rocket nozzle designed to improve efficiency and performance across a range of altitudes. Unlike traditional bell-shaped nozzles, aerospike nozzles maintain optimal expansion of exhaust gases, allowing for better thrust in varying atmospheric conditions. This design helps reduce drag and increases fuel efficiency. The key feature of aerospike nozzles is their ability to adapt to changes in air pressure. As a rocket ascends, the nozzle's shape allows the exhaust to expand more effectively, which can lead to higher speeds and reduced fuel consumption. This technology has been explored in various spacecraft and launch systems.