Pizza toppings are a great way to customize your pizza and make it your own. Olives, anchovies, and onions are all popular pizza toppings that can be found on many pizzas. Olives are a small, salty fruit that is usually black or green in color. Anchovies are small, salty fish that are usually found in cans or jars. Onions are a vegetable that come in many varieties and are often used as a topping for pizzas.