The Psion Organiser II is a pocket computer that comes with a language (Organiser Programming language or OPL), several applications, mass storage and RS232 capability.

The language OPL allows machine code, memory resident extensions. It has database facilities for saving and retrieving data in a structured way. OPL code automatically overlays through the procedure structure. The code is translated so the language runs very rapidly, on many applications it runs faster than an AT running GW BASIC.

The applications that come in the machine's ROM include a simple database, diary, calculator and alarms.

Mass storage devices can be plugged in either of the two slots on the side and includes datapacks, Ram packs and Flash packs.

The top slot is available for hardware/software devices. Psion has released an RS232 interface, aprinter, a bar code reader and a magnetic card swipe. A number of third parties have developed additional hardware devices.