CentOS vs OpenBSD: What are the differences?
Developers describe CentOS as "The Community ENTerprise Operating System". The CentOS Project is a community-driven free software effort focused on delivering a robust open source ecosystem. For users, we offer a consistent manageable platform that suits a wide variety of deployments. For open source communities, we offer a solid, predictable base to build upon, along with extensive resources to build, test, release, and maintain their code. On the other hand, OpenBSD is detailed as "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.
CentOS and OpenBSD can be primarily classified as "Operating Systems" tools.