The Network Effect (Theodore Vail) – the idea that certain things only have value if lots of people use them. Network Effects describes how the value of a good or service increases as more people start to use that good or service.

Feedback Loop Theory (Norbert Wiener) – tracking successes in things as a pattern and finding specific patterns in these movements. Feedback loops provide information to an organization about system successes and problems. Success results in a positive feedback loop and problems create a negative feedback loop. Sharing information to help companies make money through predictive human behavior and target specific audiences.

Dunbar Number (Robin Dunbar) – a limit to the number of people that someone can maintain good relationships with. Relationships where the person knows each person individually and personally.