Aspirin, Kleenex, velcro, hoover, post-it... Chances are, you have used at least one of these words during the last week – maybe even the last day. What else do they have in common? They all are – or started out as – trademarks. You likely knew that about Google and Kleenex, but did you have any idea that “heroin” had started out as a trademark belonging to Friedrich Bayer & Co at the end of the 19th century?