The term "Federal Bureau" refers to a government agency or department that is responsible for performing specific functions and duties related to a particular area. These departments are part of the executive branch of the federal government, and they operate under the authority granted by Congress through legislation. Some examples of Federal Bureaus include the Federal Bureau of Investigation (FBI), the Central Intelligence Agency (CIA) and the Environmental Protection Agency (EPA). These bureaus are responsible for carrying out specific missions related to national security, intelligence gathering or environmental protection respectively.