Senkou-Sen is a term used in the context of Ichimoku Kinko Hyo, a popular technical analysis tool in financial markets. It refers to the "leading span" and consists of two lines: Senkou Span A and Senkou Span B. These lines help traders identify potential support and resistance levels, as well as the overall trend direction. The Senkou Span A is calculated by averaging the Tenkan-sen and Kijun-sen lines, while the Senkou Span B is derived from the average of the highest high and lowest low over a specified period. Together, they create a cloud-like formation that traders use to make informed decisions.