In my personal experience, I first heard of it 1 year ago in a online forum game, people sold gold for Bitcoins, around March, gave it no importance at first. Now im kinda utterly commited to it. Really an interest subject of study.
I first heard about bitcoins last the year 2015 when I was once a member of the community in which bitcoins was used as the money for donations. At first I was confused what is this thing and later on I have discovered many things about bitcoins. I have no regret, I have known bitcoins because bitcoins have helped me a lot.