Using WHOIS
WHOIS is a huge database that contains information regarding every website on the internet. It contains common information such as who owns the website, their email address, and some other information. A website called domaintools.com
offers a nice WHOIS interface, but all the data comes from ICANN's service.
Note
The Internet Assigned Numbers Association (IANA) delegates the registration of domains and assignment of IP addresses to five different Regional Internet Registries (RIRs) around the world. These provide information to WHOIS about your target websites.
ARIN represents the United States, Canada, the Caribbean Islands, and North Atlantic Islands.
LACNIC is used for Latin America, as well as some portions of the Caribbean.
RIPE is for Europe, the Middle East, and Central Asian registration.
AFRINIC is the registrar for Africa and parts of the Indian Ocean.
APNIC is the registrar for portions of Asia, as well as the Oceanic rim.
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