Handheld electronic games are interactive electronic games, often miniaturized versions of video games, that are played on portable handheld devices, known as handheld game consoles, whose controls, display and speakers are all part of a single unit. Rather than a general-purpose screen made up of a grid of small pixels, they usually have custom displays designed to play one game. This simplicity means they can be made as small as a smartwatch, and sometimes are. The visual output of these games can range from a few small light bulbs or LED lights to calculator-like alphanumerical screens; later these were mostly displaced by liquid crystal and vacuum fluorescent display screens with detailed images and in the case of VFD games, color. Handhelds' popularity was at its peak from the late 1970s into the early 1990s before declining. They are the precursors to the handheld game console.

A handheld game console, or simply handheld console, is a small, portable self-contained video game console with a built-in screen, game controls and speakers. Handheld game consoles are smaller than home video game consoles and contain the console, screen, speakers, and controls in one unit, allowing players to carry them and play them at any time or place.