This document contains lecture notes on optics, including mirrors and lenses. Key points include: - Spherical mirrors can be convex or concave, and the location and properties of images formed by each type are explained using ray tracing diagrams. - Convex mirrors form virtual, upright, smaller images closer to the mirror than the object. Concave mirrors can form real or virtual images depending on the object location. - Lenses use refraction rather than reflection, and convex lenses converge rays while concave lenses diverge them.