1. Bitcoin (BTC) This digital currency may be familiar to people interested in investing. In fact, even people who have never had the chance to invest may have heard the name of this currency because there is quite a lot of news about it. Created in 2009 by someone with the pseudonym Satoshi Nakamoto, Bitcoin has managed to hold the title of the most popular digital currency since its appearance. Not only is it popular, Bitcoin has also made it into the Top 5 digital currencies that are most wor