Oily skin is caused when you have overactive oil glands – sometimes it’s genetic and sometimes it’s a result of using the wrong skincare products – if you strip too much moisture from your skin, it compensates by overproducing oil. If you have oily skin, you’ll experience shine, enlarged pores, and blackheads. You may also be prone to breakouts (caused by oil clogging pores) and will find your makeup doesn’t last well in your oily areas.

Combination is skin is neither oily nor dry, in fact, it’s both – which means it can be confusing to diagnose. You’ll experience the main symptoms of oily skin – excess oil, clogged pores, and shine in your T-zone, but you’ll also have dry patches (with flakiness and redness) in areas such as your cheeks, jaw, or hairline.

Dryness is triggered when the skin’s surface becomes damaged and invisible cracks allow moisture to escape (and irritants to get in). The symptoms? Skin feels tight, looks dull, lacks elasticity, and feels rough and itchy – often with patches of flakiness.