Press powder comes in a compact form, where you use a flat powder puff to put on the powder. Foundation is liquid or powder makeup that people use to cover blemishes and smooth skintones. Liquid is not good on oily skin types because when it runs, it'll look really nasty. Loose powder is powder that you can buy in a small tub that you use with a powder brush. Powder is used to set foundation and to keep it from running.