The following lesson was created by Vimeo for its Vimeo Video School . It’s used here with permission. Look for a new lesson each week.
White balance is the process of calibrating your camera to show colors accurately under varying light conditions. Think of it as making sure the color white is always white so that your image doesn’t have blue or red tints. Check out the video below by antarabbit  for a good introduction to how white balance affects your video.
Many cameras come with automatic white balance and it works pretty well most of the time. Sometimes though you’ll want to adjust it yourself. You can do this a few different ways the easiest of which are presets. The most common presets are sunny, cloudy, and fluorescent, and tungsten. These balance the image color based on those general lighting conditions. Some cameras will have more presets than others so play around and test what happens when you change the presets. Just think, you’ve had the power to alter reality this whole time and you never knew it!
Certain cameras will also allow you to manually adjust the white balance. The process is usually simple but varies from camera to camera so take a look at your camera’s manual to find out where this setting is located. Usually this involves taking a picture of a neutrally colored object and then using that to calibrate the white balance. Once you do this the camera will now know that this is the color of pure white in your current lighting situation and to adjust your image colors accordingly. For a better illustration of this adjustment technique, check out the video below by E. Wilding  for an overview of how to customize your white balance.
Remember every time you enter a different location, even to just another room, make sure to re-white balance your camera so all your shots will look perfect. If you dont’ it can often shift when least expected and you end up with shots that have a totally different look from one another. With proper white balance your videos will look better and people will like you more, just kidding!