whois? what is it, basically it is a form on online identity protection for your domain name. That may sound a bit blown out of proportion, but that’s basically what it does.
Whenever you buy a new domain name and fill in your details such as your email, home address and contact number, usually this is all publicly available. this is unless you choose to buy whois, if you choose to get the whois privacy then all these details will be masked and not available to the general public.
if you want to look up the whois details of a domain you can look them up on whois.net, sometimes when your domain was bought from a web hosting company you will have to go to their site to see your whois information. So if you have recently registered a domain name, and you are unsure if you have paid for this service, I recommend you go and check.
I always pay for it, I like to have my identity as protected as possible. I have a few friends who have recently bought some domain names, and I looked up their sites on the whois site and they forgot to get this service, since then they have gone out and paid for it!