If you perform a search in Google for WHOIS, you’ll get a bunch of results, but normally the first one is whois.net. By visiting www.whois.net, you can not only find out who owns a certain domain name, but also when it was purchased and more importantly, when it is due to expire.Looking up a domain name on www.whois.net is very simple. All you have to do is enter in the web address you want to look up and presto – all the information you wanted will appear. For example, if you look up the website address for the WHOIS site, you will find out some important information. In the screen shot below, we can tell that the domain name was purchased in 1997 and they have paid for it through 2018 (so no luck trying to buy it out from under them anytime soon!).While WHOIS is a great reference for when you want to find information about someone else’s website, but it can be a problem when it’s the other way around. When purchasing a domain or even afterwards, most companies provide a private registration benefit that will remove any personal information about the owner.I recently did an experiment where I purchased two new domain names and set up email accounts for each domain name using the format info@domainname.com. I then let my personal information be displayed on www.whois.net for one of the sites and purchased the security feature for the other site. (Note: The security feature displays a third party’s information instead of your own, like the one for Domains By Proxy shown below.)The first site, with all of my information displayed to the public, started receiving spam mail within 1 week of posting the information. Then, even when I removed the information a couple weeks later by purchasing the privacy package, I still continued to receive junk mail on the original email address.The second site, however, has not received any junk mail in its email account. While this could be a coincidence, I would strongly advise using the privacy feature whenever you register a new domain name to reduce the risk of receiving an inbox full of junk mail. Also, it just keeps your personal information private, which is better since everything and anything is being hacked these days.One other site that I really like is the WHOIS lookup from DomainTools. When you do a WHOIS lookup, you get a lot more information than you do from WHOIS.NET.In addition to the usual info, you get some extra data like the server type, SEO score, HTTP response code, hosting history, registrar history, IP history and more. The history items all require you to pay a subscription fee, but even without paying, you get a great deal of info about the domain. Enjoy!