The Customize menu contains commands for customizing the 3ds Max user interface (UI).
You can create a custom user interface layout, including custom keyboard shortcuts, colors, menus, and quad menus. You can load or save all of these things individually in the Customize User Interface dialog, or you can load or save all of them at once, using schemes. Schemes allow you to load all customized features of the UI at one time.
You can hide, float or dock, resize, and rearrange some UI elements into your own personal design. You can also lock the UI once you’ve got it set. Tools are provided in the Customize menu to load and save these custom UI files, or to revert to the startup user interface.
System preferences such as keyboard shortcuts, viewport configuration, units setup, grid and snap settings, and many important default settings, are also on the Customize menu.