3Delight uses standard Maya's lights with the exception of the Environment Light which is 3Delight-specific (ambient light is not supported). To these standard Maya lights, 3Delight adds some additional controls (e.g. exposure, light focus, ...) in the 3Delight section of each light.
A Note About Sampling
You will notice that there are no sampling parameters for light source in 3Delight (as there are none for materials too). The unique sampling parameter is defined in the render settings and acts on all shading components, including lights.