“Hi Guys and welcome to part 3 of (Understanding Lights In Maya), in this tutorial we will understand the Area Light and Volume Light. In previous parts we already covered Ambient, Directional, Spot and Point Light. Please read the Part 1 here and Part 2 Here. Ok let’s started by creating a Area light in the scene.”
http://www.cgarena.com/freestuff/tutorials/maya/understanding_lights/part3.html