What does "Marketing Funnel" mean?

Marketing Funnel:

A Marketing Funnel is a method of visualizing the process of creating zillions of prospects, then turning them into customers. Marketing starts with creating brand awareness, then gathering up individual prospects (leads), and promoting (effectively advertising) to those prospects, which then turns them into buyers. At every step along that path, the number of persons involved gets smaller and smaller (hence it resembles an actual funnel). A marketing funnel would include the whole spectrum of online and offline marketing.
Compare to Sales Funnel, which is more specific to a website.

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