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Invented in 1926 by college student Shintaro Uda, his professor Hidetsugu Yagi managed to pin his name first to this design. Please be an antenna nerd and always refer to the design as "Yagi Uda", not "Yagi". We have included Shintaro Uda in our Microwave Hall of Fame for years!
The basic concept of the Yagi Uda is that the gain of a dipole can be improved by adding passive "directors" at specific spacings from the receiving or transmitting element. Here is a very simple Yagi Uda design, courtesy of Wikipedia.
By the 1960s, Yagi Uda antennas were on the roofs of many suburban houses, to pull in signals from the cities people had moved away from. The sheer size of broadcast television antennas in the United states owed to the relatively low frequencies of channels 2 through 13 (54 to 216 MHz, or 5.56 to 1.39 meter wavelength). Typical Yagi Uda anaog TV antennas might be two meters wide back in the day.
Below, Lucille Ball and Vivian Vance try to install an antennal on the roof of Lucy's house. This is not an episode of the iconic "I Love Lucy, but the follow on "Lucy Show" after she divorced her philanderer husband Desi Arnaz. It is amusing that she keeps bumping the antenna into the power lines, but if they were actually live, she would have been unalived during this scene. According to IMDB, his episode aired in November of 1962, and eventually Lucy gets stuck in the chimney.
To show you that 100 years later, the Yagi Uda design still has legs, go to Amazon and look up Yagi antennas and you will see a wide variety that can help you pull in broadcast signals. They are mostly smaller than the old analog TV antennas, as digital TV moved up in frequency, to 470 to 608 MHz.
https://www.amazon.com/s?k=yagi+antenna&crid=1TH64SN4KGDSK&sprefix=yagi%2Caps%2C175&ref=nb_sb_ss_p13n-pd-dpltr-ranker_1_4
For now, we will lead you to Wikipedia's good description of Yagi-Uda antennas. As for an accurate history of his design, please visit the IEEE web site below (no firewall!)
References
https://en.wikipedia.org/wiki/Yagi%E2%80%93Uda_antenna
https://ieee-aess.org/post/blog/history-column-yagi-antenna