Taxes are when the government takes a percent of your money and pays for services. Also it is when you pay more than the bill and you pay it annually. Like if you buy a candy bar for 1.00 with 7% tax is 1.07$.
Discount and mark up
Discount is when you have to pay less than usual. Mark up is when you have to pay more than usual. Mark bought a discounted chocolate bar on Black Friday. And a marked up candy bar the day after. The bar usually costs $1.00 on Black Friday he bought it for $.03 less and on the day after he bought it for $1.03. So the percentages for each were 3%