<P> The history of tablet computers and the associated special operating software is an example of pen computing technology, and thus the development of tablets has deep historical roots . The first patent for a system that recognized handwritten characters by analyzing the handwriting motion was granted in 1914 . The first publicly demonstrated system using a tablet and handwriting recognition instead of a keyboard for working with a modern digital computer dates to 1956 . </P> <P> In addition to many academic and research systems, there were several companies with commercial products in the 1980s: Pencept, Communications Intelligence Corporation, and Linus were among the best known of a crowded field . Later, GO Corp. brought out the PenPoint OS operating system for a tablet computer product: a patent from GO corporation was the subject of an infringement lawsuit concerning the Tablet PC operating system . </P> <P> The tablet computer and the associated special operating software is an example of pen computing technology, and the development of tablets has deep historical roots . The first patent for a system that recognized handwritten characters by analyzing the handwriting motion was granted in 1914 . The first publicly demonstrated system using a tablet and handwriting text recognition instead of a keyboard for working with a modern digital computer dates to 1956 . </P> <P> Tablet computers appeared in a number of works of science fiction in the second half of the 20th century, with the depiction of Arthur C. Clarke's NewsPad appearing in Stanley Kubrick's 1968 film 2001: A Space Odyssey, the description of the Calculator Pad in the 1951 novel Foundation by Isaac Asimov, the Opton in the 1961 novel Return from the Stars, by Stanislaw Lem, and The Hitchhiker's Guide to the Galaxy in Douglas Adams 1978 comedy of the same name, all helping to promote and disseminate the concept to a wider audience . </P>

When did the first tablet computer come out