A Taco is a traditional Mexican dish composed of a maize or wheat tortilla folded or rolled around a filling. The fact that a taco can be filled with practically any meat, fish, shellfish, vegetable, cheese or anything that fits on a tortilla, allows for its great versatility and variety. A taco is generally eaten out of hand, without the aid of utensils, and is often accompanied by a garnish such as salsa and often vegetables such as cilantro, onion, cabbage, tomato, or lettuce.

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http://en.wikipedia.org/wiki/Taco