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In OFDM, multiple radio carrier waves closely spaced in frequency are transmitted within the radio channel, with each carrier modulated with bits from the incoming bitstream so multiple bits are being sent simultaneously, in parallel. At the receiver, the carriers are demodulated and the bits are combined in the proper order into one bitstream. Radio direction finding – this is a general technique, used since the early 1900s, of using specialized radio receivers with directional antennas to determine the exact bearing of a radio signal, to determine the location of the transmitter. The location of a terrestrial transmitter can be determined by simple triangulation from bearings taken by two RDF stations separated geographically, as the point where the two bearing lines cross, this is called a "fix". Military forces use RDF to locate enemy forces by their tactical radio transmissions, counterintelligence services use it to locate clandestine transmitters used by espionage agents, and governments use it to locate unlicensed transmitters or interference sources.

With the information contained in two narrow bands of frequencies called sidebands just above and below the carrier frequency. Initially seen as simply another press-supported community service, a radio station became a means of hedging bets in case the new medium proved competitive with newspapers. Efforts were made to use radio in World War I, but the technology proved unreliable. Wireless sets were available in battlefield trenches, where they were reserved for emergency communication in the event of cut telephone and telegraph wires. The switch to "radio" in place of "wireless" took place slowly and unevenly in the English-speaking world. Although its translation of the 1906 Berlin Convention used the terms "wireless telegraph" and "wireless telegram", by 1912 it began to promote the use of "radio" instead.

AM stations broadcast in monaural audio; AM stereo broadcast standards exist in most countries, but the Radio industry has failed to upgrade to them, due to lack of demand. Broadcasting is the one-way transmission of information from a transmitter to receivers belonging to a public audience. Since the radio waves become weaker with distance, a broadcasting station can only be received within a limited distance of its transmitter.

In radar, used to locate and track objects like aircraft, ships, spacecraft and missiles, a beam of radio waves emitted by a radar transmitter reflects off the target object, and the reflected waves reveal the object's location. In radio navigation systems such as GPS and VOR, a mobile receiver accepts radio signals from navigational radio beacons whose position is known, and by precisely measuring the arrival time of the radio waves the receiver can calculate its position on Earth. In wireless radio remote control devices like drones, garage door openers, and keyless entry systems, radio signals transmitted from a controller device control the actions of a remote device. HD Radio is a bridging technology designed to replace traditional FM transmission. Instead of radio waves, a digital signal is transmitted which is received by HD Radio receivers and converted into sound. Many HD Radio radios are also capable of FM reception in addition to the HD Radio standard.

The current television standard, introduced beginning in 2006, is a digital format called high-definition television , which transmits pictures at higher resolution, typically 1080 pixels high by 1920 pixels wide, at a rate of 25 or 30 frames per second. Therefore, each of the 6 MHz analog RF channels now carries up to 7 DTV channels – these are called "virtual channels". Digital television receivers have different behavior in the presence of poor reception or noise than analog television, called the "digital cliff" effect.