

Some source code is available under the Apple Public Source License while the bulk is licensed under the MIT License. The source code for X11 is available from Apple. In Mac OS X Leopard, X11 was updated to use X.Org Server (X11R7.2) rather than XFree86. "Rootless" means that X window applications show up on the Quartz desktop, appearing like any other windowed Quartz application (that is, not in a virtual desktop contained within another window). This implementation includes an XFree86 4.4 based X11 window server, Quartz rootless window manager, libraries, and basic utilities such as xterm. In Mac OS X 10.4 Tiger, Apple's X11 implemented X11 protocol release 6.6 (X11R6.6). Mac OS X 10.5 Leopard, Mac OS X 10.6 Snow Leopard, and Mac OS X 10.7 Lion installed X11.app by default, but from OS X 10.8 Mountain Lion on Apple dropped dedicated support for X11.app, with users being directed to the open source XQuartz project (to which Apple contributes) instead. In Mac OS X 10.4 Tiger X11.app was an optional install included on the install DVD.
#Xquartz maverick for mac os x
X11.app was initially available as a downloadable public beta for Mac OS X 10.2 Jaguar and later included as a standard package for Mac OS X 10.3 Panther. This includes numerous scientific and academic software projects.

XQuartz allows cross-platform applications using X11 for the GUI to run on macOS, many of which are not specifically designed for macOS. The name "XQuartz" derives from Quartz, part of the macOS Core Graphics framework, to which XQuartz connects these applications. It formally replaced Apple's internal X11 app. XQuartz is an open-source version of the X.Org X server, a component of the X Window System (X11, or shortened to simply X, and sometimes informally X-Windows) that runs on macOS.
