Photoshop Color Correction
This page covers a small tutorial on how to use photoshop for color correction.
What is it used for?
The color of images can be altered in a variety of ways. Colors can be faded in and out, and tones can be changed using curves or other tools. The color balance can be improved, which is important if the picture was shot indoors with daylight film, or shot on a camera that with an incorrectly adjusted white balance. Special effects, like sepia and grayscale can be added to an image. In addition, more complicated procedures such as the mixing of color channels are possible using more advanced graphics editors.
This video tutorial gives a basic overview of the procedure you can use to correct any images using Adobe Photoshop.