👉 XWindows, also known as XFree86, is an open source cross-platform operating system created by Microsoft in 2004. It was initially developed to run on top of Windows and was designed to be a lightweight, low-power, high-performance, cross-platform operating system. The term "xWindows" comes from the acronym XFree86, which refers to the xwindows project, a community effort started by Microsoft in 2004 that aims to create an open-source alternative to Microsoft's Windows operating system. The xFree86 project is now known as the Free Software Foundation. The definition of "xWindows" is not entirely clear but it is generally understood to refer to the Linux-based operating system created by Linus Torvalds, who founded Linux in 1991 and released it under the terms of the GNU General Public License (GPL). In summary, xWindows was a cross-platform, lightweight, low-power operating system developed for Windows that was designed to be a simple yet powerful alternative to Microsoft's Windows. It is now known as "Free Software" and its development is ongoing.