Why do we use Html5? Isnt Html enough?

Question

need to kniw the basic difference between two and how to get expert in it

Answer 1

we don't have perfect audio files in html and it was provided in html5 it is not only reason there are many improvements done in html5 and reduce the redundancy of some code and extra feature of getting more tags

Answer 2

Why do we use motorcycles? Isn't bicycles enough? ^^

Anyway, what are you refering by "Html"?
Html first specifications is quite old, and there was many step versions since ( last before Html5 was Html4.01 ), but all of them could be shortened to "Html", last version is implicitly meaning... or are you refering to Html1?

You can look at supported tags for each version in this web code (run it to read):
https://code.sololearn.com/Wc8Dz2ZjWn9N/?ref=app