Grills have grates, though griddles attribute a flat cooking surface. Everything cooked on grills can be cooked on griddles, but not vice versa. As an example, you could’t Cook dinner omelets, eggs, or pancakes due to the elevated ridges on grills. Griddles will often be sold as commercial grill forms https://www.cindersbarbecues.co.uk/cinders/get-your-grill-ready-for-national-taco-day/