Military communications or military signals deal with all facets of internal communication, or transfer of information, by military forces. Military signals encompass all branches of the armed services. The oldest military communications in existence are run by runners carrying messages between army and fleet. These signals have evolved over time to become complex and extremely reliable for the modern army.

During World War I, the United States Army Signal Corps was the sole communications system for the entire Army. From the very first shots to the last, signal order was communicated through runner radios, wire tapping, and telex machines. From the trenches to the field, messages were passed along wire, across enemy lines, and back to headquarters. As the war wore on, new technologies, such as wireless and satellite phones, paved the way for newer, more efficient and reliable military communications methods.

With the advent of the tank, soldiers no longer needed to run between positions looking for the next hole in the ground. A similar development came about with the radios of the tank itself. Soldiers could talk to each other in both tanks and on their treadmills without ever leaving their protected comfort zones. New and more modern concepts such as radio telephones and radio signals took the place of long-range radios used in the earlier military communications equipment.

High end Military communications

Radio signals were also translated into computer codes for use by military communications equipment. Encrypted radio transmissions became the means of secret message passing for decades. Encrypted radio transmissions and military signals have been the source of many computer hacking trials. New computer software radio technology was created to crack the code, but it was soon found that the same codebreaking efforts required the expertise and experience of a skilled engineer as opposed to an ordinary user. The need for a codeword hacker became one of the primary reasons for the U.S. Military's decision to replace its telex system with the more easily cracked digital computer language code, commonly called RACB.

Digital radio communications systems have become a mainstay of military and law enforcement operations around the world. Radio Frequency Identification (RFID) tags are used in everything from animal tracking to tracking cars in traffic. RFID tags provide users with additional security, by allowing them to track protected objects, locate them, and even retrieve them if they are lost. Smaller radio communications systems have been used to track individuals, though larger systems are now in use for tracking fleets of trucks and buses. In the military, these larger systems are being employed as a fail-safe means of monitoring troop movements, making the movement of soldiers within secured areas easier to monitor.

The need for higher-quality military communications equipment is not only tied to the necessity of listening in to conversations overseas but also to keeping track of troops within the United States. While the First Amendment gives citizens the right to peacefully protest, and freedom of speech is a pillar of American democracy, American military personnel have the right to be kept informed of their locations, while on duty. Modern devices designed to eavesdrop on conversations, and display data related to troop positions, have led to an increase in interoperability between different branches of the service.

Interoperability between forces operating in different geographical regions has increased because of the widespread use of smart phones, GPS, and other communication technologies. Communication between the U.S. and Armed Forces in Europe, Asia, and Africa is now much more common. As a consequence, interoperability is becoming an increasingly important issue, especially as younger, smaller teams members move between different parts of the globe. This increase in global mobility is leading to shorter periods of time that a soldier must wait before being able to communicate with their home base. For this reason, military communications equipment must be able to stay up-to-date with new technology and rapidly adapt to new environments and changing requirements.

Major defense contractor Bell Helicopters has recently been developing Future Fighting Force, which will support future planners and military communications equipment operators. The plan is to have the company's AH-1 helicopters become part of the Army's Common Capabilities and Restorerable Electronic Data Network, or CCAN. A future CCAN should enable operators to exchange radio signals over long distances, instead of using traditional radio channels. The company has also invested in a number of other technologies, most notably the Wide Area Augmentation Radio Internet Protocol, or WARAP, which is expected to replace current satellite communication systems.