Fluorescent starters are used in several different kinds of fluorescent lights. If a fluorescent light has stopped working or isn't working correctly, it's often because the starter needs to be replaced. Fortunately, they're very inexpensive and easy to install. The starter is a small plug that slots in next to a fluorescent tube, which provides the energy that makes the light fluoresce. If a light won't switch on at all, in many cases you just need a new starter.