Gann angles are named after W. D. Gann, a 20th-century market theorist. Gann described the use of the angles in the stock market in The Basis of My Forecasting Method, a 33-page course written in 1935.
For Gann the most important angle was the line which represented one unit of price for one unit of time, called the 1x1 or the 45° angle.