70s
80s
90s.
In that order.
70s brought total change in Indian cinema and story telling and gave huge actors like AB, Kaka, Dharam, VK, Shatru, Rishi, Rekha, Hema, Shabana, Parveen, Zeenat and greatest writers like Salim Javed and path breaking subjects like Ghar, Aandhi etc by likes of Gulzar.
Most influential decade with progressive characters.
80s had great parallel cinema.
90s is all fluff and glamour but no substance. Forgettable films except maybe Bombay, Fire, Earth etc.
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