If you've never paid attention to that white balance (WB) setting in your camera, you've likely encountered outdoor footage that came out really blue or indoor footage that came out really yellow. These are two of the most common white balancing issues. In most editing programs, we usually define a white portion of the image, and then the program would color correct the image to the best of its ability from there.
In FCPX, Apple has decided to go for a more all-encompassing automatic approach called color balancing. When you activate color balance, FCPX magically tries to fix the color of an image with no input from the user. When you're in a time crunch, it's amazing to be able to just highlight 50 clips in a row, and boom, have FCPX improve the color balance of all the clips at once.
Of course, if you're a colorist, or an artiste, automatic color corrections are rarely going to make you happy. We'll be covering manual color...