OpenBSD, or Open Source BSD, is a Unix-based operating system that is designed to be secure and reliable while being easy to use and maintain. It was created by the Berkeley Software Distribution (BSD) in 19993 as an alternative to UNIX System V, which at the time was considered too complex for most users. OpenBSD is free software licensed under the BSD license, meaning that it can be freely used and modified by anyone who wants to. It is known for its simplicity, security, and stability, making it a popular choice among system administrators and developers alike.