To press the right button on the mouse and release it. Also called a "secondary click," right clicking typically opens the context menu, which provides operations that pertain to the menu, file name or icon that is right clicked. For example, right clicking is the common way to find a file's properties. Any function can be assigned to a right-click menu by software.
On laptops, pressing the right button near or below 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 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.