Marcia Karen Wallace was an American actress and comedian, primarily known for her roles in television situation comedies. She is best known for her roles as receptionist Carol Kester on the 1970s sitcom The Bob Newhart Show and as the voice of elementary school teacher Mrs. Edna Krabappel on the animated series The Simpsons from 1990 to 2013, for which she won an Emmy in 1992.