What is High-definition television (HDTV)?

High-definition television (or HDTV) is a digital television broadcasting system with higher resolution than traditional television systems (standard-definition TV, or SDTV). HDTV is digitally broadcast; the earliest implementations used analog broadcasting, but today digital television (DTV) signals are used, requiring less bandwidth due to digital video compression.

High-definition (high-def) is the highest resolution offered within the digital television category. As television programming and TV sets themselves are moving from analog to digital, it’s easier to deliver movies and programming in higher resolutions. High-def content is also more often displayed in widescreen, which is similar to how it looks in the movie theater. Between standard definition and high definition, there’s a range of resolutions, but the easiest way to explain the difference is that a high-def image holds more information than a standard-definition image. This means that high-def can be up to six times clearer than what you get on DVD, which lends itself to being shown on larger screens.

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