We just learned about the Brake Pad.
Another part of a car is the Tire.
We know these are the things on the car that touch the road and spin around and make the car go.
Even though tires seem really simple, there is a lot of work that goes into making a tire that doesn't pop or slip all over, and that makes a car ride feel smooth.
When people first started making carts to sit in and be pulled by horses, they were mostly just made of wood, metal and leather so they were a very bumpy ride.
Now cars use rubber tires, that are smooth or bumpy on the outside depending on if you are driving in snow or on a race track.
There are even giant rubber tires that are made with no air in them so they can't pop.
(from: wikipedia - tire)
Kid Facts - Blast from the past: Safety Valve
