Human intelligence 

Human intelligence (HUMINT) is the process of collecting information about human targets, with or without interaction with them, using many techniques such as taking photographs and video recording. There are three models of human intelligence:

• Directed Gathering: This is a specific targeting operation. Usually, all the resources are meant to gather information about a unique target
• Active Intelligence Gathering: This process is more specific and requires less investment, and it targets a specific environment. 
• Passive Intelligence Gathering: This is the foundation of human intelligence. The information is collected in opportunistic ways such as through walk-ins or referrals. So there is no specific target, except collecting information and trying to find something.