What is the 'CIA Triad' in information security?

Confidentiality means to protect data from unauthorized disclosure (encryption, access controls, classification). Integrity is to ensure data is complete, accurate, and unmodified (checksums, digital signatures, audit trails). Availability means ensure systems and data are accessible when needed (redundancy, backups, DR, DDoS protection). Security controls are evaluated against the CIA triad. A DDoS attack violates Availability. Data breach violates Confidentiality. Tampering with transaction records violates Integrity. Banks must balance all three as excessive security controls can impair availability.