Formal methods refer to a set of techniques and tools used for designing, verifying, and testing complex systems and software applications. These methods are widely used in engineering, computer science, and other technical fields where precision and reliability are critical. Synonyms for formal methods include formal verification, formal specification, formal modeling, and formal analysis. These methods involve using mathematical notations, logic, and other formalisms to describe and analyze the behavior of a system. Formal methods are particularly effective at identifying errors and potential vulnerabilities early in the development process, leading to more reliable and secure systems. Other related terms include formal reasoning, formal semantics, and formal methods in software engineering.