Slivercasing, or narrowcasting, is the transmission of video programming to a niche audience, often through relatively inexpensive means like streaming video over high-speed connections. By this means, programming what would not generate enough interest or revenue for broadcast can be made available to a small but highly dedicated audience of viewers. Slivercasting can be profitable because it enables highly targeted advertising aimed at specific demographics or interest groups.
Podcasts, webcasts, narrowcasts and the rest of the casts: Glossary
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