a drinking straw (or "straw") is a utensil used to consume cold drinks such as milk shakes, smoothies, cola, and fruit juice. drinking straws are usually made from plastic that is formed into a tube. to use a drinking straw, a person places the straw in a glass that contains a liquid and then sucks the straw with their mouth. straws are mainly plastic, but some straws are paper or cardboard to protect the environment.