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 ...

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 ...

Dana Miranda is a Certified Educator in Personal Finance, creator of the Healthy Rich newsletter and author of You Don't Need a Budget: Stop Worrying about Debt, Spend without Shame, and Manage Money ...