I always thought these goverment agencies were the same if you know the difference tell me please thank you.
The FBI's mission is "to protect and defend the United States against terrorist and foreign intelligence threats and to enforce the criminal laws of the United States." The primary function of the CIA is "to collect information about foreign governments, corporations, and individuals, and to advise public policymakers." So, FBI = domestic and CIA = international. Read more about it here: http://funadvice.com/r/c3ok5gki9.
one does internal investigations(FBI) and one does out side the country things(CIA)
FBI - Investigates crimes Nationwide / CIA - Gathers Intelligence Internationally