A marketing funnel is a strategic framework that represents the customer journey from initial awareness to final conversion. It visualizes the stages a potential customer goes through, starting with awareness of a product or service, moving towards consideration and evaluation, and ultimately leading to a purchase decision. The funnel typically consists of four main stages: awareness, interest, desire, and action. Marketers use various tactics and channels to guide and nurture prospects through each stage, aiming to convert them into loyal customers.