What should people know about Yakuza?

2017 is a big year for the Yakuza series! Yakuza 0 was released back on January 24, and now Yakuza Kiwami is coming to the PlayStation 4 on August 29. Now is the perfect time to get into the series. But before people do, they may be wondering what they should know about these games. Cue an extensive explanation!