An ice cream sandwich is a frozen dessert consisting of ice cream between two biscuits, wafers, cookies, or baked goods. The ingredients are different around the world, with Ireland using wafers and the United States commonly using cookies.

A wafer is a crisp, often sweet, very thin, flat, light biscuit, often used to decorate ice cream, and also used as a garnish on some sweet dishes. They frequently have a waffle surface pattern but may also be patterned with insignia of the food's manufacturer or may be patternless. Some chocolate bars, such as Kit Kat and Coffee Crisp, are wafers with chocolate in and around them.