Oily skin is characterized by a greasy appearance. This skin type is prone to acne, large pores and breakouts. Oily skin is the result of excess sebum production. Using harsh chemicals, not suitable for your skin type can also contribute to oily skin.
Combination skin is a mixture of two skin types - dry skin and oily skin. If you have combination skin, the pores in your T-zone are larger than the rest of your face. Harsh products may clog your pores. Using a gentle cleanser is recommended.