Editing Broadcast television systems (section)

=== Pre–World War II systems ===
{{Main|Television systems before 1940}}

A number of experimental and broadcast pre-WW2 systems were tested. The first ones were mechanically based and of very low resolution, sometimes with no sound. Later TV systems were electronic, and usually mentioned by their line number: [[375-line television system|375-line]] (used in Germany, Italy, US), [[405-line television system|405-line]] (used in the UK), [[441-line television system|441-line]] (used in Germany, France, Italy, US) or [[567-line television system|567-line]] (used in the Netherlands). These systems were mostly experimental and national, with no defined international standards, and didn't resume broadcasting after the war. An exception was the UK 405-line system, that resumed broadcasts and was the first to be standardized by ITU as [[System A]], remaining in operation until 1985.