White balance tells your camera the color temperature of the environment you're shooting in. Different types of light have different colors. For example, incandescent bulbs (like what many people put in a lamp) have a very warm color. The fluorescent lights (if you're reading this in an office, look up) are a little bit cooler. Daylight is cooler yet. Before you begin shooting, you have to adjust your camera's white balance according to your setup.
One of the most important aspects of post-production is editing your video footage. Of course, that involves cutting and splicing together your b-roll, interviews, and lifestyle footage to create your story. But it also involves adjusting other visual elements, like white balance, color, and clarity, to accurately represent the story you want to relate. These edits will create the entire look and feel of your video, which highly affects its branding. After all, when you think of an Apple store, you don’t think of dim, romantic lighting, so make sure your color edits reflect your creative vision.