What is a trend line on a scatter plot?

A trend line on a scatter plot, also known as a line of best fit, is a straight line that represents the general trend or pattern of the data points in the scatter plot. It helps to visually summarize the relationship between two variables plotted on the scatter plot. Trend lines are useful for identifying the direction and strength of the relationship between the variables, as well as predicting the value of one variable based on the value of another.