Debian is a free operating system (OS) for your computer.
The OpenBSD project produces a free, multi-platform 4.4BSD-derived UNIX-like operating system. Emphasizing portability, standardization, coherency, correctness, proactive security and integrated cryptography. It comes with almost 9000 software package in its ports, including a custom X11 environment (Xenocara), desktop environments, web and multimedia applications, compilers and programming languages. It also harbours the OpenBSD-maintained software projects OpenSSH, LibreSSL, OpenIKED, OpenBGPD