1 - About
The Raspberry Pi is a computer that is about the size of a deck of cards, yet it is capable of running a Linux distribution on its ARM 11 processor. The Raspberry Pi also supports USB, Ethernet, audio, HDMI, and RCA video output. But most importantly, the Raspberry Pi provides a 26-pin header that connects the computer to the outside world, through general-purpose input/output (GPIO) pins that can drive LEDs, read switches and other electronic signals, and connect to a wealth of inter-integrated circuit (I2C) devices, universal asynchronous receiver/transmitter (UART) devices, and more.
2 - IDE
Bluej enable coding directly on the raspberry without the need of a second computer