The Sony PalmTop PTC-500 was released in Japan in 1990 and was one of Sony's earliest portable computers. The keyboard-less, book-sized, portable computer features handwriting recognition, with the stylus connected via a wire. The screen can recognise handwritten text in Japanese or English. With a 16-bit processor and 320 kilobytes of built-in RAM memory, the computer was said to be capable of recognizing English letters and more than 3,500 complex Japanese characters - in more than one million variations of individual writing styles.

The computer uses "fuzzy logic" - a set of reasoning rules that enables a computer to process information expressed in vague and imprecise terms. ''Fuzzy logic" has been used in other Japanese computers to imitate human reactions for functions that require flexible responses, such as starting and stopping subway trains.

Manufacturer: Sony Corporation
Date: 1990

This exhibit has a reference ID of CH35249. Please quote this reference ID in any communication with the Centre for Computing History.