The odd … ellipsis

From Slate: "The punctuation mark of the ellipsis is perhaps the most unusual mark in the English language, for punctuation marks are designed to convey meaning by indicating relationships between ideas, but the ellipsis does the exact opposite. It simply indicates that something has been omitted. Sometimes, this omission is poignant, as in J. Alfred Prufrock's lament 'I grow old…I grow old…' which invites the reader to imagine what has happened to the him in the spaces between him growing old. Sometimes, it is simply a placeholder, as happens when a fellow messager is typing on the other end of the line."