What we've got is a set of complete environments for you to use in your renders. Each of thirty separate presets comes complete with a high resolution 360 degree seamless skydome, matching UberEnvironment2 HDRI presets for high quality global illumination as well as diffuse and specular lights which line up perfectly with the sun's position in the sky. Simply double click your desired preset, and you're scene will be enveloped in it's own atmosphere with no need for additional lighting!