Lou: You gonna order something, kid?
Marty McFly: Ah, yeah… Give me - Give me a Tab.
Lou: Tab? I can't give you a tab unless you order something.
Marty McFly: All right, give me a Pepsi Free.
Lou: You want a Pepsi, PAL, you're gonna pay for it.
Kids today watching Back to the Future would be just as confused as Lou. What the fuck is a Tab? What the fuck is Pepsi Free?