RAMS is an acronym for Reliability, Availability, Maintainability, and Safety. 
- Reliability is a product's or system's ability to perform a specific function and may be given as design reliability or operational reliability.
- Availability is the ability of a system to be kept in a functioning state.
- Maintainability is determined by the ease with which the product or system can be repaired or maintained.
- Safety is the requirement not to harm people, the environment, or any other assets during a system's life cycle.