This is the most famous (and misunderstood) tool. It is a spiral of numbers starting with "1" at the center. Cardinal cross numbers (East, West, North, South) and ordinal crosses create "resistance levels."
If you want a good text on Gann courses, read John J. Murphy’s Technical Analysis of the Financial Markets (Chapter on cycles & Gann) or search for “Gann: Fact or Fiction?” by Robert Fischer – but keep your wallet closed until you see verifiable proof. wd gann courses
: Specifically tailored for commodity markets, which Gann believed were more profitable than stocks because they follow seasonal trends and the law of supply and demand. It covers charting, Gann Angles, the Square of Nine , and hex charts. Amazon.com This is the most famous (and misunderstood) tool