The term "combo" has multiple meanings depending on its context.
1) In a general sense, combo can refer to any combination or mixture of two or more things. For example, someone might order a cheeseburger combo meal at a fast food restaurant which includes a burger with cheese and a side item such as fries or a drink.
2) Combo is also used in reference to a special offer that combines multiple products or services for one price. For instance, a phone company might offer a "combo deal" that bundles together a mobile phone plan with internet service at a discounted rate.
3) In some video games, the term combo refers to a series of moves executed in quick succession to defeat an opponent or achieve a high score. For example, a player might have a "special move" combo that allows them to perform several powerful attacks without taking any damage.