Many people believe the pico de gallo — a mix of tomatoes, onions, pepper, and cilantro — served in many Mexican restaurants is the only type of salsa there is. Salsa is, quite simply, Spanish for sauce, and these sauces can be as varied as sauces in any other cuisine.
For fish tacos, nothing beats a fruit-based salsa. I love the flavor of this spicy grilled pineapple salsa. It comes together quickly, and can be used for other dishes as well!