Osborne 1 is the world's first commercial and successful portable computer. Developed by Adam Osborne and designed by Lee Felsenstein. It was introduced on April 3, 1981. After its introduction, it attracted great attention, sold approximately 11000 units and brought about 20 million dollars of revenue to its firm. The Osborne 1 includes a 500-page user manual that explains both its operating system and some office software produced for it. It weighs 10.7 kg and costs $ 1795. It is the ancestor of all today's laptop and portable computers. Although portable computers were built before Osborne 1, these products could not leave the prototype stage.