This document provides information about basic skin training. It discusses the three layers of skin (epidermis, dermis, hypodermis), factors that cause skin aging (both internal and external factors), skin types (normal, oily, dry, combination), and skincare routines for different skin types including cleansing, toning, serums, moisturizing and SPF. It also lists ingredients that work well for specific skin concerns such as dullness, enlarged pores, and wrinkles.