Does not matter what type of Operating System you have
There are many advantages to the domain name system. Obviously having only one unique domain is brilliant. You may have multiple websites on one IP address however there can only be one of each domain.
Just like there can be only one social security number or one address for a house. Ironically the trademark system, the legal system, does not have this advantage. Many companies can use the same trademark, typically in different industries but still different as long as they are not confusingly similar. And there are other legal requirements.
So if you want your domain name you better get it now before it is gone, of course there are still plenty of word combinations available. However there can only be one of each, use this godaddy promo code to get a discount. Obviously it does not matter if you have a windows or linux server, a domain is a domain.