The Nine Dot Puzzle

The following is a classic "thinking outside the box" puzzle. Can you connect all nine dots below by drawing exactly four straight lines, without lifting your pencil or tracing back over any line?

Give it a try before you click below for the answer.

If this puzzle looks familiar, it's because it dates back at least as far as Sam Loyd's 1914 Cyclopedia of Puzzles. When I said this was a classic "thinking outside the box" puzzle, that was a clue. You have to think outside the bounds of the box created by the nine dots to come up with a solution.