HP-48 Series

HP-48 Series

The HP-48 is a series of graphing calculators using Reverse Polish notation (RPN) and the RPL programming language, produced by Hewlett-Packard (HP) from 1990 until 2003. The series include the HP-48S, HP-48SX, HP-48G, HP-48GX, and HP-48G+, the G models being expanded and improved versions of the S models. The models with an X suffix are expandable via special RAM (memory expansion) and ROM (software application) cards. In particular, the GX models have more onboard memory than the G models. The G+ models have more onboard memory only. The SX and S models have the same amount of onboard memory.

Note that the similarly named HP-48GII (2004) is not really a member of the series, but rather much more closely related to the HP-49G and HP-49G+.

The hardware architecture developed for the HP-48 series became the basis for the HP-38G, with a simplified user interface and an infix input method, and the HP-49G with various software enhancements. Likewise, the hardware and software design of the HP-48 calculators are themselves strongly influenced by other calculators in the HP line, most of all by the HP-18C and the HP-28 series.