"Mister Kotter" is a popular American television sitcom that aired from 1975 to 1979. The show follows the life of Gabe Kotter, a high school teacher who returns to his alma mater to teach a group of underachieving students known as the Sweathogs. The series highlights the challenges and humorous situations that arise in the classroom. The character of Gabe Kotter is portrayed by actor Gabe Kaplan, while the Sweathogs include memorable characters like Vinnie Barbarino, played by John Travolta. The show is known for its comedic take on education and the relationships between teachers and students, making it a beloved classic of its time.