A medium by which a message is conveyed from one person to another.

A facility which embraces the personnel and equipment to provide signal communication by any particular means or combination thereof. COMMEL, Division Signal Battalion.`

Is the principal means of communication in tactical units. It use for command, fire control, exchange of information and administrative purposes between and within units.

It is used as the principal means of communication in all armed forces. This means of communication embraces all equipment used for laying recovering wire, battery operated and sound-powered telephones, switch boards and teletype equipment when their use is authorized.

This means of communication is the most rapid one. It is most frequently used for maintaining command, control, contact and direction in contact. The radio has one distinct advantage over other means of communication. It has a relatively high degree of mobility and flexibitly, resulting from the fact that physical circuits are unnecessary to establish communication between radio stations.

It is used to control the action of the small units. Over the years, a visual signal has been relegated to the role of an auxiliary means of communication. Any signal that is received by the eye regardless of how it is transmitted “common sense” definition of a visual signal, flags, signal flares, and smoke signals have been used throughout the ages as visual means of communication have been developed.

This means of communications is primarily to spread alarms. Normally it is used to warn troops of an impending hostile air, mechanized, or gas attack, Signal received by the unaided ear, regardless of the method of transmission, are sound means of communication. They may be transmitted by whistles, bugler, horns, weapons and other noise- making device. Prearranged messages are transmitted through this means.

A call sign that identifies all radio station operating in a particular net and using the same frequency.

Are pronounceable words that have assigned meaning to facilitate transmission by radio.

A method of establishing the communication whereby the station calling transmit the identity of the station called as well as his own identity.

A group of several station working together in the same frequency.

Combination of characters (Letters and numbers) or Pronounceable.

This call sign Identifies two or more station in particular radio net but not all stations in the net.

This call sign identifies a single call to any station within the net.