In Pixar's Cars, Mater is the rusty tow truck who becomes Lightning McQueen's friend.
Mater lives in Radiator Springs and introduces himself to McQueen after the race car is stranded there. His cheerful personality, unusual stories, and strong loyalty gradually help McQueen understand the value of friendship and community.
The character's name is a shortened form of “tomater,” reflecting the movie's playful use of automotive language. Mater is voiced by comedian Larry the Cable Guy, whose Southern-style comic delivery helped shape the character's distinctive voice.
Mater is not the town's sheriff, doctor, or race mechanic. He is a tow truck and the owner of Tow Mater Towing. His friendship with McQueen continues through the sequels, where he remains central to the story and becomes involved in international espionage during Cars 2.