Some LED drivers and dimmable fluorescent ballasts have built in dimmers.
A common technology used in this type of driver is 1-10V. As the dimmer is built into the driver the dimmer and driver are matched giving smooth flicker free dimming.
Focus SB’s 1-10v controller sits on the wall and looks like a dimmer, sending a signal to the driver to dim. It also has a push on / off function that can be used to turn the lights off completely.