The term 'Martini Extras' refers to the various garnishes that can be added to a Martini cocktail, such as olives. Olives are a popular choice for a Martini garnish, and they are typically served in a Martini glass alongside the drink. Olives are usually pitted and stuffed with ingredients such as garlic, anchovies, or blue cheese. They can also be served plain or with a variety of other garnishes, such as lemon wedges or pickled onions.