Harmonic patterns are models on price charts that contain 4 or more points-vertices (3 or more segments-edges) that correspond to a strictly defined shape and structure. The structure is characterized by the ratios of segment lengths, for which the Fibonacci ratios are performed with a high degree of accuracy. It is thanks to the use of Fibo coefficients (which, according to the discoverers of the figures, determine the harmony of the market movement) that the patterns are called harmonic. Explanation of the Harmonic Patterns trading strategy https://nsbroker.com/investment-strategies/harmonic-pattern-trading-strategy The first harmonic patterns were described in the 30s of the twentieth century. In 1935, Harold Hartley published his own course in technical analysis-a book called" Profits in the Stock Market "("Profits in the Stock Market"). Several models were mentioned in the work, but the maximum attention was paid to one, known today as the "Gartley" pattern (many sources use the names "Gartley 222"," Gartley 222", since the description is placed on page 222 of the original book"Profit on the Stock Market"). The theory of harmonic analysis of graphic figures was further developed in the works of Larry Pesavento , who described the method of pattern recognition and used the Fibonacci ratio in identifying it. His findings are published in the books "Profitable Patterns in the Stock Market" and " Fibonacci Ratios in Pattern Recognition» A significant contribution to the modern level of harmonic pattern analysis belongs to Scott Carney. He supplemented the theory with a description of several figures (Bat, Shark, Crab), defined the principles of trading strategies using harmonic models, formulated the principles of risk management, etc. His book "The Harmonious Trader" and the three-volume "Harmonic Trading" are considered today the best description of classical harmonic patterns and a guide for traders who use such figures in trading.