Another knowledge acquired for me! Since I entered this community, I have always thought that Bitcoin was the first digital currency. But upon reading this thread, it turns out that I was wrong, bigtime! It would also be interesting to know why the first ones failed, though. My guess is that, the reason why Bitcoin succeeded was because it learned from the mistakes of those ahead of it.

All I can say now is, we have to continue the success of Bitcoin, because for all its benefits, I think it's what it deserves.