In the Twitter world where it's all about trends and hashtags, one more viral trend has been taken over by netizens. Over the last few days, pictures captioned "You had to be there" have flooded the microblogging platform. The trend involves people sharing pics that capture the zeitgeist of the Eighties and the Nineties, including scenes from blockbuster movies, TV shows, old gadgets, iconic products of the era, and more.