The force in fluids described by Archimedes' principle that allows objects to float is buoyancy.

Here's how it works:

* Archimedes' Principle: This principle states that an object submerged in a fluid experiences an upward buoyant force equal to the weight of the fluid displaced by the object.

* Buoyancy: This upward force is what counteracts gravity and allows objects to float.

* Floating: An object floats when the buoyant force acting on it is equal to or greater than the object's weight. If the buoyant force is less than the weight, the object will sink.

So, in simpler terms, an object floats because the fluid it displaces weighs more than the object itself.