system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 why do websites have different endings (com, net, org) what do they mean?
gpt
Rewind back to the very early days of the internet, when it was mostly academic institutions that decided to connect themselves together so they could share information and email.  They decided that it would be useful to give connected sites a label, so that as people communicated with one another, or downloaded information from somewhere, they could tell who (or what) it was they were downloading from... So the "top level domain" was born.

.edu was for educational institutions.

.gov was for government.

.mil was for military

.com was for commercial organizations

.org was for non-profits.

.... And then each country got their own TLD as well....... .us for United States, .au for Australia, .uk for UK, etc. etc. etc...... And back in the original version of all this, you actually had to provide documentation to prove you were what you said you were, in order to use anything except a .com

But.. Now you had a way to rapidly identify what kind of entities you were interacting with.

I suspect if the internet could do it all over again, TLDs wouldn't exist.. and the entire DNS and URL schema would be made way simpler than it is..  But it's so baked in now, this is how it will still be working for the rest of our lives.