Back to the Future jokes

"Back To The Future"-Doc: You can time travel to anytime in HISTORY, Marty, but NEVER go to the year 2021.....

When you are going back to where you live from a place that is a time zone behind where you live:

"Looks like I am going back to the future!"

Why did the hobo go back to the future?

To stop himself from wasting all his money on a rigged casino machine.

How do you know you're following a DeLorean? The white line disappears.