A double-click is the act of pressing a computer mouse button twice quickly without moving the mouse. Double-clicking allows two different actions to be associated with the same mouse button. It was developed by Bill Atkinson of Apple Computer (now Apple Inc.) for their Lisa project. Often, single-clicking selects (or highlights) an object, while a double-click executes the function associated with that object. Following a link in a modern web browser is accomplished with only a single click, requiring the use of a second mouse button, "click and hold" delay, or modifier key to gain access to actions other than following the link. On touchscreens, the double-click is called "double-tap"; it's not used as much as double-click, but typically it functions as a zoom feature. ("triple-tap" sometimes used to zoom the whole screen.) On icons On most systems, double-clicking an icon in the file manager will perform a default action on the object represented by the icon. Double-clicking an application program will launch the program, and double-clicking a file icon will open the file in a default application for that file's type or format. On text In many programs, double-clicking on text selects an entire word, and possibly other characters, as defined in word boundaries. (In X Window, it will also copy that piece of text into a buffer separate from the system clipboard, as with all selected text. The selected text is not also put into clipboard until an overt cut or copy action takes place. A person can retrieve the information from this buffer, which is not the system clipboard, later by pressing the middle mouse button.) Difficulties New mouse users or the elderly often have difficulty with double-clicking due to a need for specific fine motor skills. They may have trouble clicking fast enough or keeping the mouse still while double-clicking. Solutions to this may include: Click once to select and press Enter on keyboard (on Windows systems). Using keyboard navigation instead of a mouse. Configuring the system to use single clicks for actions usually associated with double-clicks. Configuring the system to allow for more delay time between the two clicks for it to be registered as a double-click (See below for how to on several operating systems) Remapping the double-click function to a single click on an additional button, for example the often unused middle button. This effectively creates a Unix style 3-button scheme of select/action/context.