SHODAN is a search engine that lets you find specific computers (routers, servers, etc.) using a variety of filters. Some have also described it as a public port scan directory or a search engine of banners.
Web search engines, such as Google and Bing, are great for finding websites. But what if you're interested in finding computers running a certain piece of software (such as Apache)? Or if you want to know which version of Microsoft IIS is the most popular? Or you want to see how many anonymous FTP servers there are? Maybe a new vulnerability came out and you want to see how many hosts it could infect? Traditional web search engines don't let you answer those questions.
Locate any devise that's connected to the Internet.
Shodan is the world's first computer search engine that lets you search the Internet for computers. Find devices based on city, country, latitude/longitude, hostname, operating system and IP.
Any body knows how does it works?