Cyber security refers to technologies, processes, and practices designed to protect networks, devices, programs, and data from attacks, damage or unauthorized access. The top threats include phishing, malware like viruses and ransomware, identity theft, and business email compromise. To protect information according to the CIA triad, systems aim to maintain confidentiality by restricting access, integrity by preventing unauthorized data changes, and availability by ensuring authorized access. Common vulnerabilities are exploited by threats. Cyber security professionals work to mitigate these threats and vulnerabilities through technical and organizational measures.