A primer is a cream, gel, or powder applied to the skin before makeup to create a smooth surface and improve the longevity of the makeup. There are different types of primers, including foundation primer, eyelid primer, under-eye primer, lip primer, mascara primer, and mattifying primers. A foundation primer may work like a moisturizer, or it may absorb oil with salicylic acid to create a less oily, more matte appearance. Some contain antioxidants such as A, C, and E, or other ingredients such as grape seed extract and green tea extract. There are water-based and silicon-based foundation primers, and some may also have sun protection factor (SPF) . Some foundation primers are tinted to even out or improve skin tone or color, while others give a pearlized finish to make the complexion more light reflective. Primers can enhance many parts of your beauty routine, including eyeshadow, foundation, tinted moisturizer, and mascara.