A date-and-cost line chart tracks a commodity's changing price over time. Economists use such diagrams to display broad market trends and predict future prices. Businesses that restock continually use ...

If you understand the definition of a mathematical function, a good way to judge it is that any line drawn parallel to the y-axis intersects with the values in the function’s curve only once. The same ...

Is your chart boring? Try Excel’s people chart to liven things up. Susan Harkins shows you how. A people chart is an infographic, which leads me to a second definition. An infographic tells a story, ...