Answer 1

http://www.differencebetween.net/technology/internet/difference-between-htm-and-html/

I learned something new from this. 🤔

Answer 2

tbh, its googleable question.

ok, htm vs html right ? they're basicly the same. you can use any of them by you own preference. cmiiw but html was an alternative file format for htm back in a day.

the only problem i was encountering is somehow index.htm doesnt registerd as "entry point" unlike index.html, i cant remember which webserver i was using. but its years ago. probably already patched by now.

Answer 3

Taste Yes, you are right, some servers on hostings do not perceive this or that ending of writing of a file name