High Definition TV

High-definition television (HDTV) is a digital television broadcasting system with a significantly higher resolution than traditional formats (NTSC, SECAM, PAL). While some early analog HDTV formats were broadcast in Europe and Japan, HDTV is usually broadcast digitally, because digital television (DTV) broadcasting requires much less bandwidth if it uses enough video compression. HDTV technology was first introduced in the US during the 1990s by a group of electronics companies called the Digital HDTV Grand Alliance.
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TV system using an increase in the number of screen lines for a sharper picture.