How does the United States gather intelligence? Here are some of the key ways:
HUMINT - Human Intelligence
All information is obtained directly from human sources. Activities range from direct reconnaissance and observation to the use of informants and spies.
SIGINT - Signals Intelligence
This type of intelligence is made up of, either individually or in combination, all communications intelligence, electronics intelligence, and foreign instrumentation signals intelligence. With SIGINT, targets may be detected and located through airborne direction-finding techniques. Signal analysis often picks up enemy operational plans.
ELINT - Electronic Intelligence
Electronic intelligence focuses on noncommunications signals intelligence, such as radar. Signal identification is performed by analyzing the collected parameters of a specific signal and matching it to known criteria, or recording it as a possible new emitter.
COMINT - Communications Intelligence
This form of intelligence deals with messages or voice information derived from the interception of foreign communications. Intelligence is pulled from listening for voice communications, usually over radio but also from telephones or from wiretaps.
MASINT - Measurement and Signature Intelligence
Intelligence is pulled from analysis of data that locates, identifies or describes distinctive characteristics of targets. MASINT information is extremely technical, costly to maintain and often difficult to use.
UGS - Unattended Ground Sensors
Technologies were developed during the Vietnam War. Sensors were made from sonobuoys used by the Navy and from intrusion detectors developed for the Army.
S&TINT -- Scientific and Technical Intelligence
This intelligence comes from collecting, analyzing and interpreting scientific and technical information from newspapers, magazines, books and broadcasts, as well as phone directories, films, maps and charts.
IMINT - Imagery Intelligence
Imagery intelligence uses information reproduced optically or electronically and comes from photography, radar sensors, infrared sensors, lasers and electro-optics. This intelligence is highly credible but can be expensive.
OSINT - Open-Source Intelligence
This type of intelligence is publicly available information appearing in print or electronic form, including radio, television, newspapers, journals and the Internet.