Cetane

Imagine you have two different kinds of toys to play with. One toy is really easy to play with, you just press a button and it starts moving. The other toy is a bit harder, you have to put in more effort to make it start moving.

The same thing happens with gasoline for cars. The gas has to start moving in the engine to make the car go, and cetane is a measure of how easy it is for the gas to start moving.

If the gas has a high cetane number, it means it can start moving really easily and your car will move faster and smoother. If the gas has a low cetane number, it means it takes more effort to get the gas moving and your car might not move as well.

So, cetane is just a way to measure how easy it is to start and move gasoline in a car engine.