Is it a subdomain?

[Valerij]

Hello, me and my friend had a long discussion about this;

www.domain.com/user <----- Is this a subdomain?

www.sub.domain.com <----- Or is this a subdomain?

Or maybe both are?

And, if number one is not a subdomain, what do you call it then?

[felgall]

The first is a directory within the domain.

The second is a subdomain.

At bluehost a subdomain points to a directory within the domain and so both of your examples may return the exact same page if that is the directory that the subdomain points to.

[Valerij]

Thats what I told him, but he still dont wanna give up, because of what you said at the end, I think hes confused. So I made an real example;
daniel.valerijgames.com

dhost.com/idani

Both are exact same page just tell him with big letters that the first one is a sub domain and the the second one is not. And would be very helpful if you knew what we call the second way since the first is a subdomain.

[felgall]

The second one is directly referencing a directory within the domain rather than having its own domain or subdomain reference. It is sometimes referred to as the path, directory path, or folder.

At http://www.felgall.com/brsgen29.htm I have a description of what all of the component parts of a web address are including all of the optional pieces that are seldom used.