The 1980s brought the advent of the video cassette recorder (VCR), and advancing technology meant increasingly affordable VCRs. When VCRs became within reach for most schools' budgets, this marked beginning of a decline in filmstrip use. Video instruction combined the ease of the filmstrip with automatically synchronized audio and full motion video. By the early 1990s, the vast majority of filmstrip producers that were not equipped to compete with video either closed or sold their businesses.

https://en.wikipedia.org/wiki/Filmstrip

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