Casio PF-3000, launched in 1983 was the first hand held computer. Casio PF-3000 was called a digital diary. In 1984 Psion of United Kingdom introduced the first pocket computer. It was called the Psion Organiser I and it had a calculator, a clock and a flat-file data base. The product was not based on any operating system. Thus began a new era of an entirely different world of hand held computers which came to be called palm pilots or palmtops or Personal Digital Assistants. Apple, Palm Computing and many others jumped in with their versions of hand held computers. Palm Pilot, launched at the end of 1990s, became the most well known PDA. Nokia then came out with their 9000 Communicator in 1996, a mobile phone with PDA functionality. The product topped the global sales chart. Soon others brought out their own product range such as Nokia N-Series, the RIM Blackberry and Apple iPhone to create smartphones, a new category of phones.