This is the beaglebone black. It is a tiny board based around the Sitara AM3358 Arm Cortex A8 microprocessor. It has 512MB DDR3 RAM plus 2GB eMMC on board flash storage. There are also two PRU 32bit microcontrollers, USB client, USB host, Ethernet, HDMI and two 46 pin IO headers.
A nice feature is that you can plug it into your PC as a USB client device and access it via TCP/IP over the USB cable. There is an integrated development environment called cloud9 that allows you to program the device right from inside your web browser. You can literally get started in less than five minutes.
The Beaglebone has three I²C interfaces, two of which are available on the IO headers. This tutorial talks you through how to use them and shows how they can be used to interface with the PCA9685 16 channel PWM driver board.
A basic tutorial on how to export GPIO pins and switch a digital output such as an LED by manipulating the file system. Later tutorials build upon this showing how to manipulate the file system with program code.
Take a look at the plastic case that I have designed and 3D printed for the Beaglebone Black. You can download the stl file and print one yourself, or order one from Civrays via the MakeXYZ website.