Without fail, every dermatologist we’ve ever spoken to has told us to use retinol (aka retinoids, Retin-A, granactive retinoids). Whether we’re asking for advice on dealing with oily skin, acne, uneven skin tone, fine lines or just how to get healthy, glowing skin, they’ll always name drop this miracle ingredient and insist that retinol is the answer to all our skincare problems. Think of it as the Beyoncé of the skincare world – a skincare star.

But with any skincare cure-all as powerful as retinol, comes a lot of questions and inevitably some confusion. So, it’s essential to know the basics: what it is, how it works, when to use it, as well as the answers to the slightly more complicated questions like, WTF is the difference between a retinoid and retinol? We spoke to two expert dermatologists for the full low down on how to use retinol; Dr. Doris Day, celeb dermatologist and author of Beyond Beautiful, and NYC-based Board-Certified dermatologist, Dr. Shereene Idriss, who specializes in facial aesthetics and rejuvenation. Here’s everything you need to know about introducing retinol into your routine: