White balance is a feature that changes the colour balance in your pictures, making it cooler or warmer depending on the light in which you are shooting. You can choose from many modes depending on the light conditions, including Cloudy, Shade, Fluorescent, or Automatic.
If you don't want to rely on automatic white balance settings, you can adjust the white balance according to the surrounding conditions. For example, if you are shooting in a sunny spot, set the white balance to "Sunny".