Is default.aspx a .Net equivalent to an "index" file?

I have just started to work for a new company as a web developer, previous research has led me to find out their site is built in asp.net which isn't a problem, I just dont have any experience in this, all my experience is html, css, php and Js.

Upon gaining access via ftp, I noticed there is no traditional index.bla, so I went to the hom开发者_C百科epage on their website, and in stead of index, it was default.aspx.

Is this "default.aspx" file the .Net replacement / equivalent of an index file, and does it work in the same way?

Yes. In IIS (the web server) you can specify which files will be shown when a directory (like the root, when accessed through http://www.sitename.tld/) is requested.

You can configure which files will be shown and in what order. Like here (IIS 6):

So when a user requests a directory on that site, IIS will search for "Default.htm", if that isn't found it'll look for "Default.asp" and so on. If none of the default documents are found, you will either see the directory's contents (disabled by default) or an error saying you can't see the directory's contents.

In Apache this is set through the DirectoryIndex directive in httpd.conf.

Yes. index is an arbitrary name that Apache defaults to. The index page can be named anything, and with IIS it is usually default.