Always wanted to know this, always been afraid to Google it because I figured it would report me for self harm or something like that.

So, 1. What would happen if, while driving on the highway at highway speeds, you grab the gear shift knob and put it in park? Would it just lock up all the wheels or what?

And 2. What would happen if, also while driving on the highway, at highway speeds, you turn the car off (turn the key and remove it)?

I feel like both should be impossible while the car is in motion. But somehow I don't think they are. And to a gearhead, these are probably really stupid questions. But as someone who barely understands how cars do what they do... I'm curious.