Charlie is a C-list Homer acquaintance that many get confused with Sam. In his first two word appearance ("Domestic situation") he has a wildly different voice from usual, much gruffer.

Charlie fits the middle of all Simpsons roles, where he is easily recognised but very little is known about him. His actual relevance in episodes is rare, with his most memorable scene being when he is arrested for conspiracy after apparently joining a militia.

Of course it could be argued that his most known appearance is when he breaks Homer's concentration, despite not saying a word:

Somewhere down the line we'll cover Charlie's wife and son, but by then you'll have even forgotten he exists.
This post is part of my "Every Simpsons Character Ever" series. For a list of my rules in this project, click here.