A sales funnel is a strategic marketing concept that represents the journey a potential customer takes from the initial awareness of a product or service to the final purchase. It is a visual representation of the various stages a customer goes through, starting from the top of the funnel where they become aware of the product, moving down to the middle where they consider and evaluate it, and finally reaching the bottom where they make a purchase decision. The goal of a sales funnel is to guide and nurture leads, converting them into paying customers through targeted marketing efforts at each stage of the funnel.