Solaris, also known as OpenSolaris, is a Unix-based operating system that's designed for enterprise environments. With its roots dating back to the 1980s, Solaris has evolved over the years, incorporating cutting-edge technologies like DTrace, ZFS, and SMF. The operating system's open-source nature has made it an attractive option for developers, who can modify and distribute the code under the Common Development and Distribution License (CDDL).