The ST Book (also written as STBook) is a notebook-sized laptop released in October 1991 by Atari Corporation.[4] It is based on the Atari STE. The ST Book is more portable than the previous Atari portable, the STacy, but it sacrifices several features in order to achieve this: notably the backlight, and internal floppy disc drive. [verification needed]
The screen is highly reflective. It supports the 640×400 1-bit mono mode only without an external video port. It gained some popularity as being the most utterly portable full-featured computer of the day (slim, light, quiet, reliable, and with a long battery life, even by modern standards for all 5).
The ST Book is shipped with a modified version of TOS 2.06.