History of Radio.

The term "radio" can refer to either the electronic appliance that we listen with or to the content that plays from it. In any case, it all started with the discovery of radio waves—electromagnetic waves that have the capacity to transmit music, speech, pictures, and other data invisibly through the air. Many devices work by using electromagnetic waves, including radios, microwaves, cordless phones, remote controlled toys, televisions, and more.

The Roots of Radio
Scottish physicist James Clerk Maxwell first predicted the existence of radio waves in the 1860s. In 1886, German physicist Heinrich Rudolph Hertz demonstrated that rapid variations of electric current could be projected into space in the form of radio waves, similar to light waves and heat waves.
In 1866, Mahlon Loomis, an American dentist, successfully demonstrated "wireless telegraphy." Loomis was able to make a meter connected to a kite cause a meter connected to another nearby kite to move. This marked the first known instance of wireless aerial communication.
But it was Guglielmo Marconi, an Italian inventor, who proved the feasibility of radio communication. He sent and received his first radio signal in Italy in 1895. In 1899, he flashed the first wireless signal across the English Channel, and two years later received the letter "S," which was telegraphed from England to Newfoundland (now part of Canada). This was the first successful transatlantic radiotelegraph message.
In addition to Marconi, two of his contemporaries, Nikola Tesla and Nathan Stubblefield, took out patents for wireless radio transmitters. Nikola Tesla is now credited with being the first person to patent radio technology. The Supreme Court overturned Marconi's patent in 1943 in favor of Tesla's.

True Broadcasting Begins
KDKA (1920): Often credited as the first commercial radio station, it broadcasted the results of the presidential election.
1920s Boom: Rapid growth in radio stations; the medium became popular for music, news, and entertainment.
Regulation and Standardization (1930s)
Federal Radio Commission (FRC): Established in 1927 in the U.S. to regulate the airwaves and reduce interference.
AM vs. FM: Amplitude Modulation (AM) was the dominant format until Frequency Modulation (FM) emerged in the late 1930s, offering better sound quality.
The Golden Age of Radio (1930s-1950s)
Dramas, comedies, and news: Radio became a primary source of entertainment and information.
World War II: Radio played a crucial role in disseminating news and propaganda.
Television and Decline (1950s-1960s)
As television became popular, radio's audience declined. However, it adapted by focusing on music, talk shows, and specialized formats.
Resurgence and Diversity (1970s-Present)
FM Radio: Became more popular, especially for music.
Talk Radio: Emerged as a new format, gaining a dedicated audience.
Digital Revolution: Internet radio, satellite radio, and podcasts have transformed how we consume audio content, allowing for niche programming and on-demand listening.

With thanks from thoughtco