The term "funnel" is a common metaphor in marketing and sales to describe the process of customer acquisition and retention. In its simplest form, a funnel consists of various stages that describe a potential customer's journey from initial awareness of a product or service to the final purchase and beyond. Typical phases of a funnel are awareness, interest, consideration, purchase and loyalty.

In the awareness phase, the target group becomes aware of the product or service for the first time. This can happen through advertising, social media or other marketing channels. In the interest stage, potential customers begin to actively search for more information. In the consideration stage, they compare different options and consider buying the product. The purchase is the fourth phase in which the transaction takes place. The final phase, loyalty, concerns long-term customer loyalty and possible recommendations.

The funnel is not only a descriptive representation of the customer path, but also serves as an analytical tool. Companies use it to understand at which points potential customers "drop out" and do not continue the process. This analysis makes it possible to develop targeted marketing measures to improve the conversion rate at each step of the funnel.

In digital marketing, specific types of funnels are often used, such as the sales funnel, the email marketing funnel or the content marketing funnel, each of which is tailored to the specifics of the various communication channels and sales strategies.