1. Bar chart: Bar charts are suitable for comparing values across categories or groups. They can be used to show sales by region, revenue by product category, or customer satisfaction scores by department. I've found that bar charts are particularly effective when there are a limited number of categories, and the focus is on comparing their values.
2. Line chart: Line charts are ideal for displaying trends over time or continuous data. They can be used to show stock prices over a period, website traffic over several months, or sales growth over quarters. In my experience, line charts are most effective when there is a clear trend or pattern in the data that needs to be highlighted.
3. Pie chart: Pie charts are used to represent proportions or percentages of a whole. They can be used to show the market share of different competitors, the distribution of sales by product type, or the allocation of a budget across various departments. Pie charts are most effective when there are a limited number of categories, and the focus is on illustrating their relative proportions.
A useful analogy I like to remember is that bar charts are like a horse race, where you want to see who comes first, second, or third; line charts are like a journey, where you want to see how things progress over time; and pie charts are like a pizza, where you want to see how the slices compare to the whole.