ASP.NET - How do users in my organization's network connect to web pages hosted.

I have hosted some webpages using IIS on my web server.

Now, how do the other users within my organization's network connect to the web pages that I've hosted.

I mean do they use the same URL that I use i.e.

http://localhost/Website1/

or should they use something else?

You need to have your system's administrator configure your ip address to a domain name in your company's network dns configurations.  Then, set your web server's IIS entries Host Header for your site to that domain name.

No, they cannot navigate to localhost.  That always refers to the local machine.