A trend line is a straight line that is drawn on a graph to represent the general direction of data points over time. It helps to visualize patterns in data, making it easier to identify whether values are increasing, decreasing, or remaining stable. Trend lines are commonly used in various fields, including finance, economics, and science, to analyze trends and make predictions. To create a trend line, data points are plotted on a graph, and a line is fitted through them, often using methods like least squares. The slope of the trend line indicates the rate of change, while its position shows the overall trend. Analysts use trend lines to forecast future values based on historical data.