Dedicated handheld are portable devices with built-in games. Being very popular since very early in videogame history, these devices can be built in many different shapes, technologies and colors.
The most popular handhelds were made using very cheap processors and an LCD screen, like the Tiger Electronics handhelds and the Game & Watch.
Some of these handhelds have a cartridge/expansion slot, but their main purpose to be a self-contained device, not a portable console.
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