A freedom lawn is an equal and opposite reaction to high maintenance, high input lawns and involves no inputs like fertilizers or weed killers.
Freedom lawns are made up of a "survival of the the fittest" host of grasses and other plants sometimes referred to as weeds. When mowed high and regularly, a freedom lawn can provide aesthetics similar to lawns with more intense maintenance programs.
Even a freedom lawn could benefit from some compost once in a while though. An unhealthy abundance of certain lawn weeds could deplete the soil of it's nutrients, so topdressing with compost or using a compost tea could prevent the soil from becoming barren.