Network security is the practice of protecting computer networks and the data transmitted across them from unauthorized access, breaches, or cyberattacks. This includes implementing measures like firewalls, encryption, intrusion detection systems, and access control to safeguard both the network infrastructure and the data it carries. Network security is essential for ensuring the confidentiality, integrity, and availability of information within a network, and is crucial for protecting organizations, businesses, and individuals from potential security threats and vulnerabilities.