The greatest achievements of mankind: Number of years it took  each product to gain  50 million users  Airlines Cars Telephones Electricity Credit Cards v  ATMs  68yrs 62yrs S0yrs 46yrs 28yrs 22yrs 18yrs  Computers MobilesInternetds YouTube Facebook Twitter  Porn  hub  14yrs 12yrs yrs 4yrs 4yrs 3yrs 2yrs 19 days The greatest achievements of mankind
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