Project Insight was designed to predict and eliminate threats before they can happen by using upgraded Helicarriers linked to the targeting satellites. However, this included many important people, innocents and the Avengers. This was due to HYDRA secretly infiltrating S.H.I.E.L.D. Project Insight's targets were chosen using an algorithm designed by Arnim Zola to identify anyone who could be a threat to HYDRA, using the personal information available online.
Project Insight was first introduced to Steve Rogers by Nick Fury, who appeared to support the idea. However, after the discovery of encrypted S.H.I.E.L.D. files relating to Project Insight onboard a S.H.I.E.L.D. ship, Captain America and his allies discovered that Project Insight was controlled by HYDRA moles within S.H.I.E.L.D., who planned to use the Helicarriers to eliminate anyone who they deemed was or could become a threat to HYDRA, based on Zola's algorithm. Zola's algorithm used the data available about people online to analyze and predict their behavior; Insight thus not only targeted current threats to HYDRA, such as Tony Stark, but also those who could at some point become a threat to HYDRA, which could include a high schooler with a perfect score on his SAT's, according to Jasper Sitwell.
Captain America, Falcon, Black Widow, Maria Hill, and Nick Fury were able to take control of the Hellicarriers' targeting systems by replacing the computer chips that connected them to S.H.I.E.L.D. targeting satellites, and reprogrammed them to fire on each other.