Psion was started by David Potter in 1980, initially as a Company named Potter Scientific Instruments. The name Psion was created by adding ON to PSI. Psion at first created software for Sinclair Research and their ZX80 and ZX81 computers.
By 1983 Psion were also working on developing business applications for IBM Compatible computers and the Sinclair QL computer. They developed the powerful business software suite Easel business graphics, Archive database, Quill word processor and Abacus spreadsheet package that was included with the purchase of a Sinclair QL.
By 1984 Psion were also developing and manufacturing handheld mircoprocessor computers when they launched their revolutionary Psion Organizer that was first sold for £99 British Pound. The Psion Series 3 was introduced in 1991 which quickly became their biggest selling product.