What's the Use of the Menu Key?

The ▤ Menu key, also known as Apps key, is meant to be a application-specific context menu key. It is invented by Microsoft

In desktop (file manager), you can press 【▤ Menu r】 to rename, 【▤ Menu d】 to delete, 【▤ Menu p】 to show info/properties, etc.

In Firefox, you can press 【▤ Menu c】 to copy, and 【▤ Menu p】 to paste. Also works in terminal and most other apps.

Set Menu key to a easy-to-press Spot

The menu key isn't positioned in the best spot. You can make it so. Or, if your keyboard doesn't have the ▤ Menu key but have Fn instead, here's what you can do.

You can make the Caps Lock to be the ▤ Menu key.

• On Linux, use xmodmap. 〔►see Linux: xmodmap Tutorial〕.
• On Mac OS X, use “Seil”. 〔►see Mac: Key Remapping, Keybinding Tools〕.
• On Microsoft Windows, use AutoHotkey. 〔►see AutoHotkey Useful Scripts〕

Or, buy one of the Batman Keyboards, so you can set a thumb key to do ▤ Menu.

When you buy a keyboard, never get one that has Fn key in place of ▤ Menu key. Because, the Fn key is hardwired, you cannot remap in OS. If you don't like its preset multimedia functions, it becomes a useless key on one of the most important spot. Like, a dead horse squatting in front yard.

Menu Key in Emacs

See: Emacs: How to Define Menu Keys.