1- shodan
shodan is a very dangerous engine that shows you the Internet connected devices and displays them on a map divided into several countries and penetrates several unprotected devices or have low protection.
Through this engine you can access the Internet-related surveillance cameras, as well as other devices such as printers, databases, industrial control systems and many other devices.

2- zoomeye
ZoomEye is a engine that contains two powerful detection engines Xmap and Wmap that target devices and websites in cyberspace.
Although it is considered a "hacker-friendly" search engine, it is not designed to start attacks on network devices or websites.

3- beenverified
If you need specific information about someone (whether potential room partner or potential date), you may get more information by checking and learning more about it with this service.
Public records have been checked to collect information so you can access them in one convenient report.

4- censys
The underlying technology behind Censys was designed by researchers at the University of Michigan. Their original goal was to provide researchers a way to measure whether Internet security was actually improving. To do this, they needed to track security vulnerabilities on each server and an accessible device on the Internet, and gather as much data as possible about those hosts. The result is a searchable map of the Internet, which has become a powerful tool for security researchers.