In a Car, On a Bus— WHY?

Have you ever wondered this- why are we IN a car but ON a bus?To help you remember this in a more logical manner, try this:
-We usually step up the bus, so we are ON it, right?
-We don’t step up a car or a taxi, we get into them. So we are IN a car/taxi.
What about trains?You can use “on” the train and “in” the train for different scenarios.1. To tell someone you are aboard the train.

I am already on the train- see you in 10 minutes.

2. Inform someone of your exact position.
-I am in carriage B. Look for me there.
– I left my wallet in the train.
-You can find the homeless lady sell packets of tissue paper in the train.