A coda is a concluding segment of a piece of music, a dance, or a statement. It's usually short and adds a final embellishment beyond a natural ending point. Like this.
Coda comes from the Latin word cauda, meaning "tail," and it's good to think of it as a tail tacked onto something that in and of itself is already a whole. If you tell a story about your crazy experience getting lost in the country and sleeping at a farmer's house, you might add, as a coda, that the farmer ended up visiting you too, a year later.