*Emacs* functions can be bound to keyboard / mouse events that use a number of different modifiers.

* *Shift*
* *Control*
* *Meta* 
* *Alt*
* *Super* 
* *Hyper*

Not all input devices (/keyboards/) will have keys for all of these modifiers.

For environments in which the input device does not supply all of the modifier keys (*Shift*, *Control*, *Meta*, *Alt*, *Super*, *Hyper*), you can use one of the *Emacs* //event-apply-*-modifier// functions to simulate the addition of a single modifier to the next input  /event/ (keystroke, mouse click, etc...)

Standard *Emacs* supplies the following functions (and key bindings) to perform this simulation:

* `event-apply-shift-modifier' -- (##C-x @ S##)
* `event-apply-control-modifier' -- (##C-x @ c##)
* `event-apply-meta-modifier' -- (##C-x @ m##)
* `event-apply-alt-modifier' -- (##C-x @ a##)
* `event-apply-super-modifier' -- (##C-x @ s##)
* `event-apply-hyper-modifier' -- (##C-x @ h##)

These functions can be invoked before a keystroke / mouse event so as to manually /add/ a single modifier to the next keystroke / mouse event without requiring the modifier key to be present.

For example:

To simulate entering the keyboard event ##H-a## (##<HYPER>## + ##<a>## keys pressed simultaneously), you could enter:

   C-x @ h a

To simulate entering the keyboard event ##s-TAB## (##<SUPER>## + ##<TAB>## keys pressed simultaneously), you could enter:

   C-x @ s TAB

==Combinations of multiple modifiers==

To manually add more than one modifier (For example: ##A-C-H-a## - ##<ALT>## + ##<CTRL>## + ##<HYPER>## + ##<a>##) so as to simulate the pressing of more than one modifier key
simultaneously, use the [Lisp:event-apply+.el (event-apply+.el)] library.