The Publish Web Site command, available only in the commercial versions of Visual Studio and not
in the Express edition, is similar to the Copy Web Site option in that it creates a copy of the website
you can use for deployment. However, it’s different in that it enables you to precompile the application,
which means all the code in the Code Behind of your ASPX pages, controls, code files in
App_Code, and so on are compiled into .NET assemblies; files with a .dll extension, stored in the
bin folder of your site. The main benefits of precompiling are source protection (others with access
to the server can’t look into your source) and an increased performance the very first time a page is
requested. Pages that are not precompiled are compiled on the fl y when they are requested the first
time, which takes a little bit of time. Remember that regular visitors to your site will never be able
to see the source of your application. All they’ll be able to see is the final HTML that gets sent to the
browser.