MissingRemote posted CableCARD Tuner Essentials Guide
A quote from the article:
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At a higher level, the technology was developed to protect consumers from being forced into having to rent set top boxes (STB) at increasing fees from cable companies (or MSOs) without an alternative. From a home theater PC (HTPC) perspective, it meant the ability to natively tune high definition programming from a cable provider (previously the options were only analog cable, or digital over the air broadcasts).
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