Final answer:
A bar graph represents the number or percent of individuals in each category, and the space between the bars is used to visually separate the categories. Bar graphs can represent both class frequency and class relative frequency.
Step-by-step explanation:
In a bar graph, the length of the bar for each category represents the number or percent of individuals in each category. Bars may be vertical or horizontal. We use bar graphs when we want to compare categories or show changes over time. The space between the bars in a bar graph can vary and is typically used to visually separate the different categories. Bar graphs can represent both class frequency and class relative frequency.