Composition in photography involves framing the subject and elements within an image. There are 8 common rules of composition: 1) Fill the frame by removing empty space, 2) Eliminate distractions, 3) Follow the rule of thirds by placing subjects off-center, 4) Center subjects to create symmetry, 5) Incorporate leading lines, 6) Leave space around the subject, 7) Create depth with foreground and background elements, and 8) Consider different camera angles beyond straight-on. Following these rules can improve visual interest, balance, and focus on the main subject.