Security Basics

This document discusses basic terms related to information security and cryptography. It defines the three pillars of information security as confidentiality, integrity, and availability. Confidentiality means only authorized individuals can access information. Integrity means data cannot be altered without authorization. Availability means information systems are functioning and information is accessible when needed. The document also defines basic cryptography terms like encryption, decryption, cryptographic keys, message digests, digital signatures, public key infrastructure, and digital identity certificates. It explains how these concepts work to provide security for information.