FIPS 140, or Federal Information Processing Standard 140, is a U.S. government standard that defines security requirements for cryptographic modules - hardware or software components that perform encryption or decryption. Organizations handling sensitive government data must use cryptographic modules validated under this standard to ensure data confidentiality and integrity. FIPS 140 covers areas such as physical security, cryptographic key management, and self-testing. Compliance is mandatory for federal agencies and often adopted by private sector organizations to meet high security standards.