Is it correct to say "riding a bus"?

Okay, so about "riding a bus" versus "riding on a bus"... is it really that big a deal? Honestly, I've used both and never really thought twice about it. I mean, riding a bus just sounds so normal, right? Like, "I'm riding the bus to work tomorrow," totally natural. It gets the point across.

But then there's riding on a bus, which feels a little more... specific? Like, you're really picturing yourself on the bus, maybe looking out the window, feeling the bumps in the road. You know?

That explanation about larger versus smaller vehicles makes sense, I guess. I always say "in a car," never "on a car." That sounds totally bonkers! And, come to think of it, I say "on a train" and "on a plane," too. Huh. I never actually realized I was doing that until now. It's funny how these little grammar things work, isn't it?

I remember this one time, I was riding the bus – or on the bus, I guess – to visit my grandma. It was a long ride, and this little kid kept staring at me. Maybe I had something on my face? Anyway, the point is, I definitely wouldn't have said, "I was riding in the bus to visit my grandma." That just sounds weird!

So, yeah, both are probably fine. Just pick whichever one feels right in the moment. Unless you're writing a super formal paper or something, then maybe stick with the "on" for bigger vehicles. But in everyday conversation? I don't think anyone's gonna care.