Coefficients are numerical values that multiply variables in mathematical expressions, particularly in algebra and statistics. They indicate the strength and direction of the relationship between variables. For example, in the equation y = mx + b, the coefficient m represents the slope of the line, showing how much y changes for a unit change in x. In statistics, coefficients are used in regression analysis to quantify the relationship between independent and dependent variables. A positive coefficient suggests a direct relationship, while a negative coefficient indicates an inverse relationship. Understanding coefficients helps in interpreting data and making predictions based on mathematical models.