A bar chart is a graphical representation of data that uses rectangular bars to compare values across distinct categories. The length or height of each bar is directly proportional to the quantitative value, count, or frequency it represents. These bars can be oriented vertically or horizontally along a coordinate system where one axis displays the discrete categories being compared and the other axis provides a calibrated numerical scale. Widely used across statistics, business reporting, and scientific research, bar charts provide an intuitive visual method for analyzing differences, rankings, distributions, and patterns among distinct groups.