Bar charts, histograms, and pie charts can help your audience understand your ideas, results, and conclusions quickly and clearly. To compare different data samples or to show how individual elements contribute to an aggregate amount, use bar charts. A bar chart represents each element of a data sample as one bar. Look at the bar chart, question and sample answer and do the exercises to improve your writing skills.
![Bar Bar](http://learnenglishteens.britishcouncil.org/sites/teens/files/describing_a_bar_chart.jpg)
Look at the key, which typically is in a box next to the graph or chart. It will explain symbols and colors used in the graph or chart. In a line graph of the 'Number of Pants Sold in June,' a blue line might display the number of blue pants sold per day during the month, the red line the number of red pants, and the brown line the number of brown pants. Such a line chart can show not only how sales changed from day to day, but a quick glance shows the popularity of each color. Similarly, in a bar graph, the blue rectangle displays the blue pants sold that month, the red rectangle displays the red pants, and the brown rectangle displays the brown pants.You can put the bars next to each other in a monthly chart that just displays the relative sales of each color, or you can stack the three color bars on each other to display next to similar bars for other months. Then the bars not only show the change in sales over time, but also the change over time in the relative proportion of each color sold. In a circle, or pie chart, the blue portion of the circle is the proportion of total pants sold that were blue, the red is the proportion that were red, and the brown is the proportion that were brown.