A directional antenna consisting of two or more parallel resonant antenna elements in an end-fire array. The antenna was invented in 1926 by Shintaro Uda of Tohoku Imperial University, Japan, with a lesser role played by his colleague Hidetsugu Yagi.

Yagi antennas were first widely used during World War II in radar systems by the Japanese, Germans, British and US. After the war they saw extensive development as home television antennas. It is also used for point-to-point fixed communication links, in radar antennas, and for long distance shortwave communication by shortwave broadcasting stations and radio amateurs.