Most computer operating systems (such as Windows, MacOS, Linux, ChromeOS) recognize certain “Control Keys” as shortcuts to perform common actions or tasks. So a “Control Key” is really a command telling the operating system to perform a specific action or task. The “Control Key” command (action or task) is executed when the user holds the “Control” key (often labeled as “Ctrl” or “Ctl”) and types a letter (like “C” or “X”) while the Control key is still being held down. The Control key can be released after the letter key is released. So the typical execution of a Control key happens as follows:

• Press and hold the Control Key (typically labeled as “Ctrl” or “Ctl”)
• Press and release another letter key (such as “C” or “X”)
• Release the Control Key

Typically, the second step (pressing and releasing the letter key) will actually execute the command (action or task) for that control key.

In the early days of computing, the meanings of these control keys could be quite different between operating systems and even between programs running on the same operating system. However, over the years, several of these control keys have become defacto standards which are the same across many operating systems and programs. The three most common are “Control-C” for Copy, “Control-V” for Paste, and “Control-X” for Cut.

• Control-C – Copy whatever is selected to the invisible clipboard
• Control-V – Paste whatever is on the clipboard to the current location
• Control-X – Cut (or delete) whatever is selected and put it on the clipboard

These three common control keys will work on almost every operating system, but there are a few others. For example, most operating systems will recognize “Control-Z” as the “Undo” command. So if you make a mistake, you can “undo” it by pressing the “Control-Z” key combination. Many operating systems will also allow you to “Redo” what you’ve undone. However, there seems to be at least two common control key combinations for “Redo”. Some operating systems (and/or programs) use “Control-Y” to perform the redo operation, but others will use “Shift-Control-Z” for redo. Additionally, the Apple Macintosh computers have used a special “Command” key instead of the typical “Control” key.

If you’re not sure what keys your computer uses, you can often play around inside a text editor (or other program) to see which keys are used on your operating system. A good place to look is the “Edit” menu (or similar). For example, this is the “Edit” menu for a text editor under some versions of Linux:

This Edit menu shows that the “Undo” action can be done with “Ctrl+Z” (Control-Z). The “Redo” action is done with “Shift+Ctrl+Z”. The Edit menu also shows that the “Cut”, “Copy”, and “Paste” actions are all done with the standard “Ctrl-X”, “Ctrl-C”, and “Ctrl-V”. This Edit menu also shows a shortcut to “Select All” using “Ctrl+A”. All of these control keys can be very helpful when working with your computer.