The FBI is the domestic intelligence and security service of the United States and its major federal law enforcement agencies. The FBI operates under the jurisdiction of the U.S. Department of justice and is a member of the U.S. intelligence community and reports to the attorney general and the director of the National Intelligence Agency. The FBI is the leading anti-terrorism, counterintelligence and criminal investigation organization in the United States, with jurisdiction over more than 200 federal crimes.

Although many of the functions of the FBI are unique, its activities in support of national security are comparable to those of the UK MI5 and the Russian FSB. The Central Intelligence Agency (CIA) has no law enforcement authority and focuses on foreign intelligence collection, while the federal Intelligence Agency (FBI) is mainly a domestic agency, with 56 field offices in major cities of the United States and more than 400 resident agencies in the United States. Smaller cities and regions in the country. In the FBI field office, senior FBI officials also act as representatives of the director of the National Intelligence Agency.

Despite its focus on the domestic market, the FBI maintains an important international presence with 60 legat offices and 15 sub offices in U.S. embassies and consulates around the world. The presence of these foreign offices is primarily for coordination with the foreign security sector and is usually not a unilateral act in the host country. Just as the internal functions of the CIA are limited, the FBI can and sometimes can conduct clandestine activities overseas. These activities usually require coordination between government agencies.

The FBI was founded in 1908 as the Bureau of investigation, or boi or Bi for short. In 1935, its name was changed to the Federal Bureau of investigation (FBI). The FBI headquarters is the J. Edgar Hoover building in Washington, D.C.

In 1896, the State Bureau of criminal identification was established to provide information to institutions all over the country to identify known criminals. The assassination of President William McKinley in 1901 made people realize that the United States was under threat from anarchists. The Department of justice and labor has been documenting anarchists for years, but President Theodore Roosevelt wants more power to monitor them.

Since 1887, the Department of justice has been tasked with overseeing interstate trade, although it lacks personnel. Before the Oregon land fraud scandal at the turn of the 20th century, it made little effort to alleviate the shortage of people. President Roosevelt directed Attorney General Charles Bonaparte to organize an autonomous investigative body, which would report only to the attorney general.

Bonaparte contacted other agencies, including the United States Secret Service, for use by personnel, especially investigators. On May 27, 1908, congress banned the use of U.S. Treasury bills by the Department of justice for fear that the new agency would act as a secret police department. Again, at Roosevelt's urging, Bonaparte moved to a formal Bureau of investigation, which would then have its own agents.

From the 1940s until the 1970s, the agency investigated espionage against the United States and its allies. Eight Nazi agents who planned to sabotage US targets were arrested and six (unilateral Quinn) executed in accordance with their sentences. During the same period, the Federal Bureau of investigation (FBI) participated in a large number of joint password cracking work between the United States and the United Kingdom, known as the "Winona project", which broke the Soviet Union's diplomatic and intelligence communication laws and regulations, enabling the United States and the British government to read the Soviet Union's communications. This effort confirmed the existence of Americans who were engaged in Soviet intelligence in the United States. Hoover managed the project, but did not inform the CIA until 1952. Another famous case is the arrest of Soviet spy Rudolph Abel in 1957. The discovery of Soviet espionage in the United States allowed Hoover to be hunted. He has long been obsessed with the threat perceived by the American left, from the organizers of the Communist Party of America's trade union to American liberals.

Since the 1930s, the FBI has been a regular presence in the mass media. The Bureau's participation varies from direct participation in the creation of film or television series to the provision of advisory services on operation and closure. [100] some of the famous portrayals of the FBI on TV are the X-Files series, which started in 1993 and ended its 11th season in early 2018, involving the investigation of supernatural phenomena by five fictional agents and fictional anti terrorist forces. (CTU) TV series 24, which is based on the model of the FBI's counterterrorism department. The 1991 film point break describes a secret FBI agent who infiltrates a group of bank robbers. The 1997 movie Donnie Brasco is based on the true story of FBI agent Joseph D. pistone infiltrating the Mafia. Quantico, a TV series in 2015, is titled with the location of the training institution of the radio and Communication Bureau. It involves probation and agents, but not all actors are completely reliable or even trustworthy in the form of performance.