This has nothing to do with security, it's called
gibberish:
http://en.wikipedia.org/wiki/Gibberish[
^].
A Web application is
always used by others, otherwise there is no point to develop it. If you simply want to give different level of access to different users, you need to introduce some user authentication:
http://www.asp.net/web-forms/tutorials/security/roles/role-based-authorization-cs[
^].
As to "copying from a physical folder": all ASP.NET code is on the server side, no one can access it through the HTTP. How well this code is protected is the matter of your Web hosting. This is the internal data, not for any Web users. As to the client side, everything is by definition fully accessed by anyone who loaded the page in client side. That's why the page works.
—SA