Free HDRI environments

HDRI environments are used to light an scene instead using the GI lighting process.

What your render plugin, in my case, Vray, is going to do is use that 360º image to simulate a 360º environment with it's own ilumination sources. Due to your GI engine is going to be desenabled during that lighting process, light is going to be generate by the brightest zones of the 360º environment, giving you a really nice and real result to your scene. It's like a real world environment.

Here there are some render examples with HDRI environment.

Now it's time to practice, practice, and render your scene changing your render settings. With some time and few tips, you can easilly improve your final renders.

Check out hdrmaps.com to find some free HDRI environments and make your own tests.