OpenBSD

OpenBSD is a free, open-source, and security-focused Unix-like operating system. It is known for its proactive security development, code quality audits, and integrated cryptographic features. The project emphasizes correctness, security, and standardization.

It is primarily used by system administrators, developers, and security professionals who require a robust and secure platform for servers, firewalls, and network devices. OpenBSD is suitable for environments where system integrity and resistance to exploits are paramount.