OpenBSD vs pfSense: What are the differences?
What is OpenBSD? Only two remote holes in the default install, in a heck of a long time!. It is a free and secure UNIX-like operating system that emphasizes portability, standardization, correctness, proactive security & integrated cryptography.
What is pfSense? An open source firewall/router computer software distribution. It is an open source firewall/router computer software distribution based on FreeBSD. It is installed on a physical computer or a virtual machine to make a dedicated firewall/router for a network.
OpenBSD belongs to "Operating Systems" category of the tech stack, while pfSense can be primarily classified under "Security".