A sales tax is extra money that customers pay to the government when they buy things at a store. If a video game costs $20 and the sales tax is 6%, you'll actually pay $21.20 at the register: the original $20 plus $1.20 in tax.

Sales taxes are how state and local governments raise money to pay for things everyone uses, like roads, parks, schools, and police departments. The store collects this tax from customers and then sends it to the government. That's why the price tag on a shelf might say $20, but the cashier rings up a higher amount.

Different states charge different sales tax rates, and some states don't charge sales tax at all. Some places don't charge sales tax on certain items like groceries or clothing because everyone needs those things. Other places charge higher sales tax on luxury items.

When you're saving up for something expensive, remember to factor in sales tax. If you have exactly $50 and want to buy a $50 toy, you might be a few dollars short at the checkout because of the added tax. Smart shoppers learn to estimate: if the tax rate is about 7%, add roughly another $7 for every $100 you spend.