telegraphy
long distance transmission of text without the physical exchange of an object
flag semaphore
telegraphy system conveying information at a distance by means of visual signals
High Speed Telegraphy
Type of radiosport
High Speed Telegraphy
Type of radiosport
International Code of Signals
international system of signals and codes for use by vessels to communicate important messages regarding safety of navigation and related matters
wireless telegraphy
method of communication