A candlestick is a graphical representation used in financial markets to display the price movement of an asset over a specific time period. Each candlestick shows four key prices: the opening price, closing price, highest price, and lowest price. The body of the candlestick is filled or colored to indicate whether the closing price was higher or lower than the opening price. Candlestick charts are popular among traders because they provide visual insights into market trends and potential reversals. They can be used in conjunction with other analysis tools, such as technical indicators, to make informed trading decisions.