Another permutation of this tactic is to register as a domain name the entire address, or URL, of a popular Web site, anticipating that a certain percentage of users will leave out the dot. Thus, "wwwamazon.com" or "wwwdisney.com" become domain names in their own right. There are hundreds of such typographical errors registered as domain names; the majority of them have been registered by just two or three typosquatters.
Source: wiktionary