MAX7219 Dot Matrix Module Red LED 4 in1 8x8 dot matrix Display with 5Pin 20cm cable
 
Dot matrix displays are something that all Arduino enthusiasts come across at some point. These displays are so popular that almost all modern outdoor LED displays use them to display characters, symbols, and images.
When it comes to controlling dot-matrix displays, there is hardly a better option than the MAX7219. It can easily control a single dot matrix and, for larger projects, it can be chained together to control two or more dot matrices.
 
The Dot Matrix Display
When we are talking about the MAX7219-based dot matrix display module, it consists of 64 LEDs connected in a row-column format so that we could easily control them with the multiplexing technique. That is why a typical single color 8×8 dot matrix unit has 16 pins, 8 for each row and 8 for each column.
 
Resources:
1. Interfacing MAX7219 LED Dot Matrix Display with Arduino
2. Control led matrix max7219 with arduino
3. MAX7219 8x8 Dot Matrix LED Module Overview