The Apple Newton MessagePad 110, codenamed Lindy, features a 20 MHz ARM 610 processor, 4 MB of ROM, 1.O MB of SRAM (480k usable), and infrared-beaming capabilities in a sleek handheld case with a 320x240 pressure-sensitive monochrome display for use with a provided stylus. Compared to earlier models, the Newton MessagePad 110 provides a rubberized housing that is slimmer and more comfortable to hold, more RAM, greater battery life, and an improved version of the NewtonOS (1.3). The Newton MessagePad was one of the first series of handheld systems, or PDAs (Personal Digital Assistants), to attempt to recognize natural handwriting and use a basic form of artificial intelligence to 'tie' relevant information together. Please note that Newtons are technically not 'Macs', as they do not operate the MacOS, and instead use the NewtonOS (also developed by Apple).