To press the right button on the mouse and release it. Also called a "secondary click," right clicking typically opens a menu of ancillary operations such as copying and pasting, viewing a file's properties and so on. Any function can be assigned to a right-click menu by software, and the menu that appears depends on the location of the screen cursor at that moment.
On laptops, pressing the right button near the trackpad is the same as right clicking. In addition, an area on many trackpads can be designated as a right-click region, and tapping there is the same as right clicking.
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There are probably five functions (arrows) users want to perform when right clicking an icon in Windows. They should all be at the top. See first-time user menu
Right clicking an icon on a Mac displays fewer options.