There are two major TV systems in the world - 525-line NTSC (used in USA, Japan and most part of South America), and 625-line PAL/SECAM/ME-SECAM (used in Europe, Far East and the former Soviet block).

Most recorders sold in one area can only record in the format that is predominantly used in that area, but some recorders can record in both formats. This option tells whether or not a recorder can record in both 525-line and 625-line mode.
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