It is also a good practice to use the comment tag to "hide" scripts from browsers without support for client-side scripts

Answer 1

I think you are new ,post your views in your feed pls
and follow this
https://www.sololearn.com/Discuss/1316935/?ref=app

Answer 2

Do you mean something like:

<script><!--
var foo = "bar";
// ...
--></script>

That's an old practice not more needed today in modern browsers (probably you even cannot find enough oldest browser wich need it) and even I guess that it could be problematic in some circumstances ^^