The clear liquid that comes out of a pimple is not pus or an infection, but rather edema, which is a fluid that accumulates in the area due to redness and swelling. This clear fluid is also known as serous fluid, which is essentially white blood cells that died fighting off the infection. While it may be tempting to pop a pimple, it can lead to scarring, infection, and hyperpigmentation. Pus, on the other hand, is composed of skin cells, bacteria, and inflammatory cells that are sent there by your immune system to fight off a localized bacterial infection in the skin. When you have inflammatory acne lesions, such as pustules, papules, nodules, and cysts, your immune system activates in this area, resulting in noticeable pus. It is important to keep the area clean and let it heal properly to avoid scarring. If you see a little blood, stop squeezing, and clean the area with alcohol.