This diagram is from The Anatomy of the Inkscape Window and this link has a lot more information on the Inkscape window so you might just want to click on this link and read all of the information.
Please note that this diagram is for v.48 and we are using the latest version which has some differences.
For example, in .48 the Command Bar and Snap Bar are just below the Menu Bar. In the current version, both bars are vertical down the right side of window.
