I needed to photograph this house which is part of park on the former land of the Van Bourgondien's of the famous Tulip fame. So I made a HDR and a straight image for illustrative purposes, since some asked what it was.
I use a program from Photomatix Pro to process my HDR images, there's a few different programs on the market and I've seen incredible results from a few of them.
HDR stands for high dynamic range. In HDR, the photographer takes multi exposures of the same scene, a camera meter exposure, and over exposure and an under exposure. The program combines the
exposures basically filling in the lost detail in the highlight and shadow parts of the image.
With the control sliders you can adjust the effects to no end.
Mostly I just enjoy getting the most detail I can in an image. But, some photographers make some outrageous images with HDR. Google HDR images to see some of the more outrageous.