OSINT (open-source intelligence) is an intellectual discipline and a set of activities, tools, and methods for obtaining and analyzing information from open sources. It is applied to specific people, organizations, as well as events, and goals.
In 1947, CIA analyst Ken Sherman reported that about 80% of the country’s information is collected from open sources on the Web. A little later, the head of the United States Remote Intelligence Agency, Samuel Wilson, said that 90% of the intelligence data is also obtained from open sources, and only the remaining 10% comes from the professional work of agents and spies.