On 2017-12-14 06:31:41 +0000, Paul said:
Your Name wrote:
On 2017-12-14 03:16:11 +0000, Wolf K said:

That's what Open With is for.

Open With is near useless if you don't know what the file actually is.
You'd have to Open With with every app you have until you found one
that could open it properly.

If you don't have any tools, and are on a desert island,
you use "Open With" "Wordpad" to figure out what something
is. It's not that hard.

Only if the file itself contains some clue within it as to what the
document type is ... many don't bother with that, so you're stuck
trying to open it in every app you have.