Dynabook
The KiddiComp concept, envisioned by Alan Kay on January 1, 1968 while a PhD candidate, and later developed and described as the Dynabook in his 1972 proposal "A personal computer for children of all ages", outlines the requirements for a conceptual portable educational device that would offer similar functionality to that now supplied via a laptop computer or (in some of its other incarnations) a tablet or slate computer with the exception of the requirement for any Dynabook device offering near eternal battery life. Adults could also use a Dynabook, but the target audience was children.