What is the key difference between a bar chart and a histogram?

• A. Bar chart shows numerical data distribution with continuous bins.
• B. Bar chart shows discrete categories with equal-width bars; histogram shows numerical data distribution with continuous bins.
• C. Bar chart uses area to represent frequency; histogram uses height.
• D. Bar chart and histogram convey the same information.

Answer: (B)

Distinguishing how bar charts and histograms encode data. A bar chart is used for categorical data: each category has its own bar, and there are gaps between bars because the categories are distinct. The bars are typically of equal width and are used to compare counts or proportions across categories. A histogram, by contrast, is used for numerical data by grouping values into consecutive intervals called bins. The height of each bar shows how many observations fall into that bin, and the bars usually touch to indicate a continuous distribution across the range of values. For example, a bar chart could show counts of students by major, while a histogram could show the distribution of test scores from 0 to 100. This aligns with the idea that a bar chart shows discrete categories with equal-width bars, whereas a histogram shows a numerical distribution with continuous bins.