Linear regression is a statistical method used to model the relationship between a dependent variable and one or more independent variables. It assumes that there is a linear relationship between these variables, allowing us to predict outcomes based on input data. The simplest form, simple linear regression, involves one independent variable, while multiple linear regression involves two or more. This technique is widely used in various fields, including economics, biology, and engineering, to analyze trends and make forecasts. By fitting a line to the data points, linear regression helps identify patterns and quantify the strength of relationships, making it a valuable tool for decision-making.