These panels are similar to ones you'd see in scrolling LED information signs, and they can be used to display text or simple animations.
Note this matrix only has red and green LEDs, they can be both turned on to make...yellow! But if you want full color excitement, check out 16 x 32 RGB LED matrices here! (They require a lot more memory and processing to manage)
This matrix has 1024 total LEDs (512 red and 512 yellow) arranged in a 16x32 grid on the front. On the back there are two IDC connectors (one input, one output: you can basically chain these together) and each panel has 4 x HT1632 matrix scanning processors on the back to manage the display mutliplexing. Note that while you can dim the entire panel to one of 16 brightnesses, you cannot individually dim LEDs to create color gradiants. But, the good news is once you write the LED on/off settings you want, the multiplexing is done for you. These displays are 'chainable' - connect one output to the next input and add an extra chip-select wire per extra panel
This is a great library has native support for this display. To use, grab an Arduino UNO and make sure that's up and running. Download this example sketch. Then power the panel with 5V, and connect the panel CLK pin to #13, CS to #12, WR to #10 and DATA to #9. If you have two panels, connect the second panel's CS to #7