Anyone who purchases fluorescent or HID lighting for commercial applications probably knows that these lights require ballasts. While some like compact fluorescent lights (CFLs) come with ballasts built in, most use external ballasts. (You can learn more about ballasts here.)
LED lighting, though, is a new field that many are unfamiliar with. So it's important to know that, while LEDs don't require ballasts, they do require something called "drivers."
Like CFLs, household LEDs typically have drivers built in, but many commercial LEDs do not. And as with fluorescent lights that need to be correctly matched to their ballasts, you need to choose the right driver for an LED. So we've put together a brief video explaining the two primary types of LED drivers: Constant Current and Constant Voltage.