Newton OS is the discontinued operating system for the Apple Newton PDAs produced by Apple from 1993–1997. Newton OS was written entirely in C++ and trimmed to be low power consuming and use the available memory efficiently. Many applications were pre-installed in the ROM of the Newton (making for quick start-up) and to save on RAM and flash memory storage for user applications.Its use of ParaGraph's handwriting recognition engine has been noted as a pioneering implementation.