A bar graph is a visual tool used to display and compare different sets of data. It consists of rectangular bars, where the length of each bar represents a specific value. The bars can be arranged either vertically or horizontally, making it easy to see which categories have higher or lower values. For example, a bar graph could show the number of students in different classes at a school. Bar graphs are helpful in many fields, such as business, education, and science. They allow people to quickly understand trends and make comparisons. By looking at a bar graph, you can easily see which products are selling well or how test scores vary among different groups.