This document compares the Arduino and Raspberry Pi boards. It notes that Arduinos are microcontrollers that directly execute simple code without an operating system, making them well-suited for interfacing with sensors and devices. Raspberry Pis are full computers that run Linux and have more functionality like independent network connectivity, but with greater overhead. A rule of thumb is to use an Arduino if a project can be described in less than two "and" statements, and to use a Raspberry Pi for more complex projects requiring more than two "and" statements. The boards can also work together, with an Arduino handling sensors and devices and a Raspberry Pi providing processing and connectivity.