The primary installation folder for IIS is "c:\inetpub" (unless you changed this during installation).
There are three services that come with IIS, each with it's own sub-folder under "c:\inetpub":
Service Definition Purpose Sub-Folder Description HTTP Hypertext Transport Protocol web server wwwroot Any files placed here are part of your local website. FTP File Transport Protocol file transfer server ftproot Any file transfers using FTP are placed here. SMTP Simple Mail Transport Protocol mail server mailroot Primarily used for sending email, although it is possible to configure this to receive email as well.