What is "whoishostingthis.com"

WhoIsHostingThis.com is a commercial website providing a web hosting search tool and also reviews and thematic comparisons of hosting providers who pay to have their services advertised. It was launched in 2007 by Stan Schroeder and Gordan Orlic and it was acquired in 2008 by London-based Quality Nonsense Ltd., with a subsequent redesign and addition of new features.