Marketing involves changing customer behavior. For start-ups, the focus is on lead generation, while established companies focus on engagement and support. Marketing brands is more effective than products. The marketing process includes research, planning, and understanding how customers behave through choice sets, hierarchy of needs, advertising effects, and lifetime value. Research shows search data may reflect true customer wants better than surveys. For example, a camera company found most searches were for waterproof cameras, so they built a waterproof housing and targeted those searchers.