Mouse chording

Mouse chording is the capability of performing actions when multiple mouse buttons are held down, much like a chorded keyboard. Like mouse gestures, chorded actions may lack feedback and affordance and would therefore offer no way for users to discover possible chords without reference. A similar feature such as a context menu would require less training.

In the X Window System, and on some laptops with integrated 2-button mice, a three button mouse can be emulated using a chorded click from both the right and left buttons which is translated into a middle click. This middle-click emulation does not enable chords which involve the middle click. The Apple Mighty Mouse does not support mouse chording due to the design of the button sensors.

One common application of mouse chording, called rocker navigation, is found in Opera and in mouse gesture extensions of Mozilla Firefox. Rocker navigation typically involves the following two mouse chords:

The operating systems Plan 9 and Oberon and the acme development environment make heavy use of mouse chording. OS/2 Presentation Manager can also use chording to copy and paste text using two buttons however Common User Access key combinations are more frequently used.

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