There are basically three types of meringues:

French: sugar is gradually sprinkled over egg whites as they are beaten.

Italian: sugar is dissolved to a 250°F syrup and then slowly drizzled into egg whites while they are being beaten.

Swiss: egg whites and sugar are heated together and then whipped to desired peak.

The secret of “hard” meringues is technique of low heat for long periods. You should think of making meringue as drying out the egg whites not baking them. For hard meringues bake at low temp (200°F) for about 2 hours. Turn off oven and let set overnight or until completely dry.

“soft” meringue as those used for desserts like baked alaska, where the whites are browned briefly.