Squashes are gourds--fleshy vegetables protected by a rind--that belong to the Cucurbitaceae family, which also includes melons and cucumbers.   Squash is a notably American food. It sustained Native Americans for some 5,000 years and then helped nourish the early European settlers. New England colonists adapted the word squash from several Native American names for the vegetable, all of which meant "something eaten raw" (though both Native Americans and colonists also ate squash cooked.) Their mild, refreshing flavor and satisfying texture make them suitable for inclusion in many different dishes.