The CIA was created in in 1947 with the signing of the National Security Act with its main job being gathering foreign intelligence. Or in other words, to find out what other countries are doing in their military,weapons, and other important things. The CIA was also formed to try to affect what's going on around the world or to stop an attack that may be happening in the near future.
Some of the main jobs that you can work in the CIA are the Director (over-sees all the things going on through-out the program and makes important decisions), the executive Director, and the Deputy Division Chiefs (over-see what is going on through-out their branch of the CIA).

The Information Review Officers (IRO) decide what events can be released to the public and what events are kept secret. There are three possible categories the event can be placed in: Confidential, Secret, Top Secret. The president gives guidelines and standards on where they can be placed.
Only the Directors of Operations go over seas. These people act like the "top secret" agents that work undercover in a different country. What you see in the movies is what the Directors of Operations do, but it isn't with all the gadgets. The agents are given a whole new identity and are put into the society in a different country. Then, from there, they are given a task to find out secret information that the country is planning for their military. The agents then report back to an analyst who then writes up a report to give to the Director.
Steve Carrel and Anne Hathaway in the 2008 movie "Get Smart"

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C.I.A. Is Not What You See In Movies

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Visit this link for fun and games about the CIA: CIA Fun