Serums are lightweight, concentrated liquids designed to help correct skin concerns, such as an uneven skin tone or texture. They’re typically water-based and often contain lightweight moisturising ingredients, such as hyaluronic acid. Serums can penetrate the skin quickly and easily as a result of their watery or gel-like texture and fluid consistency. Facial oils are oil-based liquid formulas designed to be used on the skin. They’re typically formulated with non-comedogenic botanical oils and essential oils and often include plant extracts and antioxidants. They can help to moisturise and soften the skin, nourish the skin barrier function, and help address some skin concerns, like dryness or dullness.