Is there any difference between skim coat for floor and floor hardener?

To a degree yes. The skim coat is normally laid and then polished. Its frequently colour to the customer requirements. The surface is provides a high traffic protection to the floor Its no really suitable for industrial settings like warehouse of engineering or where heavy metal wheeled vehicles will cover it. Places that would use this are Theatres etc as an example its used in the Harry Potter World in London. Additionally its also easier to wash and dry by had and machine. Hardener is normally applied in warehouses and factories. It comes in two forms metallic and non metallic. The prior is harder wearing and ideal for engineering and factory environments