Module#const_get concept hunting

Hi,

I am heavily confused with ruby’s
Module#const_get(Class: Module (Ruby 2.0.0))

(a) Checks for a constant with the given name in mod. If inherit is set,
the look-up will also search the ancestors (and Object if mod is a
Module.
) - words between *** i couldn’t get,any example would be
helpful.

(b) This method will recursively look up constant names if a
name spaced class name is provided. For example:

module Foo; class Bar; end end
Object.const_get ‘Foo::Bar’

What are the probable areas(How is that located?)where these recursive
look-ups will be happened?

(c) What are probable use-cases where I should/may think of to use this
methods?