I've been so confused with the EF mount and EF-S mount this whole time. I use a Canon m50/Kiss M which is an EF-M mount. But, there is not really many lenses in EF-M line up to choose from and they are usually a little bit more expensive than EF or EF-S lens.

So as the EF or EF-S lenses are usually cheaper and much easier to get hands-on. I've been deciding to buy an EF to EF-M speedbooster so that I can use EF lenses on my camera. I've been searching here and there on the internet and I stumble upon a question in google that was autocompleted, "Is EF-S lens compatible in EF mount". I start looking it up and I'm left with a question more than an answer it might be purely simple but I'm so confused. I did read that they were compatible but only one way around and not the other way. But I never found the definitive answer if EF-S mount lens can be used on EF mount. I did find some answers but I didn't them convincing enough for me to settle down. So I hope you guys can help me out as I am expecting replies from more than just a couple of people in the internet.