Differences between external javascript and script tag in html?

Question

What difference is there between the actual content of external javascript or using script tag in html?
Thank you for taking the time to read my question.

Answer 1

At the begining all was in html. And some dev starting to use a lot of style and script .. starting to be a ugly and unmaintanable. So they start to making external file to make all of this cleaner. And recently we got a lot of external file so they start making a lot of library all packed in 1 file. And people started to use a lot so new framework tried to make all you need into less files but you now have file where you only use a part of them but it s another story.

Answer 2

Thanks for the reply Kabe.