A podcast series usually features one or more recurring hosts engaged in a discussion about a particular topic or current event. Discussion and content within a podcast can range from carefully scripted to completely improvised. Podcasts combine elaborate and artistic sound production with thematic concerns ranging from scientific research to journalism. Many podcast series provide an associated website with links and show notes, guest biographies, transcripts, additional resources, commentary, and even a community forum dedicated to discussing the show's content.
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The cost to the consumer is low. While many podcasts are free to download, some are underwritten by corporations or sponsored, with the inclusion of commercial advertisements. In other cases, a podcast could also be a business venture supported by some combination of a paid subscription model, advertising or product delivered after sale.
People are motivated to create a podcast for a number of reasons. The podcast producer, who is often the podcast host as well, may wish to express a personal passion, increase professional visibility, enter into a social network of influencers or influential ideas, cultivate a community of like-minded viewership, or put forward pedagogical or ideological ideas (possibly under philanthropic support).