Welcome to **newRPL**!

This chapter will introduce you to what **newRPL** is and how to install it on your HP50g, HP39g+, HP39gs or HP40gs.

**[[manual:chapter1:rpl|A brief introduction to RPL]]** quickly presents **userRPL**, the predecessor of **newRPL** installed on almost Saturn or ARM HP calculator.

**[[manual:chapter1:introduction|Introduction to newRPL]]** is a brief presentation of **newRPL** features: you'll have a quick glance of what **newRPL** can do and how it re-implements the concepts at the core of **userRPL** taking advantage of the ARM processor's superior speed and power.

**[[manual:chapter1:installation|Installing newRPL]]** instructs you how to install **newRPL** or restore **userRPL** on your calculator.

**[[manual:chapter1:notation|Notation and conventions]]** presents the conventions used in the following of this manual.

**[[manual:chapter1:buildfromsource|Building newRPL from source code]]** shows how to prepare a development enviornment in case one might want to build **newRPL**, **newRPL Desktop** or a support tool from scratch.

**[[manual:chapter1:usbcomms|USB communications setup]]** deals with the configuration of the PC operating system in order to ensure the calculator is correctly recognized as an USB device able to communicate with a host computer.