what is difference between html code example

Example: what is the difference between .html and .htm files

.html is awesome and new, while .htm was used back in the old days when
microsoft wanted all file name extentions 3 charectors. But, both of the
extentions do the same thing. Since microsoft has a big homescreen and
they got their website since 198 something, there homepage is
microsoft.com/index.htm.

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