The Chikou Span is a component of the Ichimoku Kinko Hyo trading system, which is used in technical analysis for financial markets. It represents the closing price of a security plotted 26 periods into the past. This helps traders visualize how the current price compares to historical prices, providing insights into market trends. Traders often use the Chikou Span to identify potential support and resistance levels. If the Chikou Span is above the price, it may indicate bullish sentiment, while if it is below, it may suggest bearish sentiment. This information can assist traders in making informed decisions.