Palmtop PC

A Palmtop PC was an about pocket calculator-sized, battery-powered PC in a horizontal clamshell design with integrated keyboard and display. It could be used like a subnotebook, but was light enough to be comfortably used handheld as well. Most Palmtop PCs were small enough to be stored in a user's shirt or jacket pocket.

Palmtop PCs distinguish from other palmtop computers by utilizing a mostly IBM-compatible PC architecture and BIOS as well as an Intel-compatible x86 processor. Most such devices were DOS-based, with DOS stored in ROM. While many Palmtop PCs came with a number of PDA and office applications pre-installed in ROM, most of them could also run generic, off-the-shelf PC software with no or little modifications. Some could also run other operating systems such as GEOS, MINIX 2.0, Windows 1.0-3.0, or Linux.

Most Palmtop PCs were based on a static hardware design for low power consumption and instant-on/off without a need to reboot. Depending on the model, the battery could power the device from several hours up to several days while running, or between a week and a year in standby mode. Combined with the instant-on/off feature, a battery would typically last from a week up to several months in practical use as PDA.

The first Palmtop PC was the DIP Pocket PC aka Atari Portfolio in 1989.

Palmtop computers were discontinued in late 2000's as all the manufacturers shifted to tablets.

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