An ellipsis ( . . . ) has two basic uses:
To Show a Pause in Dialogue
"Did I find that joke funny? Well . . . um . . . not exactly."
To Show Omitted Words
"Once a staple of the American sitcom . . . laugh tracks . . . have largely gone extinct."
"Adding a laugh track to a television show makes viewers feel . . . they’re in a room full of laughing, happy people."