The term "bonus categories" refers to specific types of purchases that can earn you additional rewards or cash back when made with a credit card. These categories are usually designated by the credit card issuer and may include things like groceries, gas, dining out, travel, or certain online purchases. When you make a purchase in one of these bonus categories, your credit card will often give you an extra percentage of cash back or rewards points on top of any regular earn rate for that category. This is meant to encourage you to use the card more frequently and for specific types of spending, which can help you save money over time.