The Raspberry Pi is a credit-card-sized computer that plugs into your TV and a keyboard. It is a capable little computer which can be used in electronics projects, and for many of the things that your desktop PC does, like spreadsheets, word processing, browsing the internet, and playing games. It also plays high-definition video.
The Raspberry Pi has the ability to interact with the outside world, and has been used in a wide array of digital maker projects, from music machines and parent detectors to weather stations and tweeting birdhouses with infra-red cameras. Here at McGill Library, we lend Raspberry Pi's because we want to encourage the community to make the most of these amazing devices.
(from Wikipedia) Arduino is an open source hardware and software project first introduced in 2005 based on 8-bit Atmel AVR, aiming to provide an accessible way for novices and professionals to create devices that interact with their environment using sensors and actuators. Common examples of such devices intended for beginner hobbyists include simple robots, thermostats, and motion detectors.
The project is based on microcontroller board designs, which use inputs and outputs in the same way an ordinary computer does. Inputs capture information from the user or the environment while outputs do something with the information that has been captured. An input could be digital or analog, and could come form the environment or a user. Outputs can control and turn on and off devices such as motors or other computers. These systems provide sets of digital and analog input/output (I/O) pins that can interface to various expansion boards (termed shields) and other circuits. The boards feature serial communication interfaces, including Universal Serial Bus (USB) on some models, for loading programs from personal computers. For programming the microcontrollers, the Arduino project provides an integrated development environment (IDE) based on a programming language named Processing, which also supports the languages C and C++. The Arduino language is very similar to C, but provides several libraries for ease of use.
Arduino comes in a variety of different boards. Arduino boards are available commercially in pre-assembled form, or as do-it-yourself kits. The hardware design specifications are openly available, allowing the Arduino boards to be produced by anyone. In mid-2011, it was estimated that over 300,000 official Arduinos had been commercially produced, and in 2013 that 700,000 official boards were in users' hands.