The difference between http_host and server_name _asp basis

Related information:

View all of the server Variables
The significance of ServerVariables set retrieval of predetermined environment variables

Today suddenly think of each request http_host and server_name value is always the same, why do you still use two names, what is the difference between them?

There is no confirmed statement on the web, and an explanation has been found on Microsoft:

Under the Windows2000 server_name equals http_host

Under the Windows2003

>> The following * number is Request.ServerVariables ("Appl_md_path") Requested/lm/w3svc/*/root

When running "CScript adsutil.vbs Set w3svc/*/usehostname true" under CMD

server_name Computer name for Windows

When running "CScript adsutil.vbs Set w3svc/*/usehostname flase" under CMD

server_name equals http_host
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