This is a general purpose CNC or 3D printer shield for the Arduino UNO. Many hobbyists use this shield when they want to use an inexpensive Arduino UNO instead of the Arduino MEGA / RAMPS 1.4 solution.
This shield was originally designed to be used with the GRBL firmware, an open source industry standard for CNC motion control.
Another option is to configure the TEACUP firmware from the REPRAP project.
The shield is also a great general purpose stepper driver board that could be used in a variety of stepper motor projects.