What would happen if all the world's oil just disappeared? What would become of us humans?

One way to make sure it does not happen is to now look seriously for alternative energy sources.

We'd move on...in smaller numbers. Humans had survived for EONS without petroleum.

If all of the world's oil were to suddenly just disappear, then all of the industrialized nations would grind to a halt. Oil provides the energy and lubricants needed to transport everything that we use. Given sufficient warning, we could build plants that could convert coal to petroleum. This would be more expensive, but it would be able to keep society going.

i think that the "mad max" series scenario is a possibility. or at least it would be for about 20 years. after that, i dont know what would happen.

watch "the road warrior" its the second mad max movie.

..maybe our legs would get stronger from all the walking or bike peddling.People who raise horses might get rich...

What a great day that would be.
No more terrorist.

We would probably live longer because of the excerise we would be getting and the fact our air would be alot cleaner and we wouldn't be breathing polloutants that are in the air as much.

You mean like, just POOF, no oil? First panic, then a breakdown of society, then starvation. 6billion plus people would reduce down to a few million. Some areas would become completely deserted wilderness. If technology survived at all, it would be in small, scattered pockets, unavailable to the average person. We would quickly reduce to a hunter-gatherer society, and perhaps a few agrarian societies.