I have 3 machines here that the IDE menus look different (different IDE versions) and different core versions installed over time.
Remember, the IDE looks across the user storage space and builds Examples, Boards, and sub-menus dynamically.
READ this:
https://www.arduino.cc/en/guide/environment
and then note:
Documentation can take a long time to be updated... a very long time.Last revision 2015/09/07 by SM