Page "Domain name" Paragraph 60

A domain name may point to multiple IP addresses in order to provide server redundancy for the cybernetic services to be delivered ; such multi-address capability is used to manage the traffic of large, popular web sites.

More commonly, however, one server computer, at a given IP address, may also host web sites in different domains.

Such address overloading enables virtual web hosting, commonly used by large web hosting services to conserve IP address space.

IP-address overloading is possible through a feature in the HTTP version 1. 1 protocol, but not in the HTTP version 1. 0 protocol, which requires that a request identify the domain name being referred for connection.