They're little pads that are designed to slide across a variety of surfaces and they can be placed under your hands, feet, or both. They offer a few of their own unique exercises, but they're also great for making exercises more difficult.
Today's full body workout is all about sliders. It's made up of two circuits with three exercises each. Do the all three exercises of the first circuit back to back, then take a rest. Repeat one or two more times, then treat the second circuit the same way.