Security software is a broad term for computer applications designed so that agents (users or programs) can not perform actions that they are not allowed to perform, but can perform the actions that they are allowed to. Security software general requires continual maintenance and upgrades to keep pace with hackers and other malicious computer users who are constantly dreaming up new schemes.

For personal computer users, anti-virus software, spam filtering, secure web browsers and personal firewalls are examples of security software. For enterprises, network monitoring software, intrusion detection systems, content security, encryption, and secure e-commerce software are typical security tools.