This is the NeoPixel NeoMatrix from Adafruit a large board with 64 WS2812 RGB LEDs arranged in an 8x8 matrix. Each LED is capable of drawing as much as 60mA (at peak brightness the matrix can draw just over 3.5 Amps at 5 Volts), this adds up so it is suggested to use a 5V 2A power supply. For most uses, you'll see about 1-2A of current per panel.
There are two 3-pin connection ports to wire the NeoMatrix up. Solder wires to the input port and provide 5VDC to the +5V and ground pins, then connect the DIN pin to your microcontroller and make a common ground from the 5V power supply to the microcontroller/Arduino.
Additionally, you can chain as many NeoMatrix panels together as you'd like. For the second panel, connect the DIN connection to the first panel's DOUT, connect the ground pins together and power with 5V. It should be noted that after four or more panels you may run low on RAM if you're using an Arduino Uno and you may need a 5V 10A power supply for so many of these!
Every stick is equipped with a single data line with a very timing-specific protocol requiring a real-time microconroller with a 8MHz or faster processor such as an AVR, Arduino, PIC, mbed, etc. There are solder pads on the back for connecting wires or breadboard pins and two mounting holes for securing this board to many different surfaces.