Here's my story:

I had a spare Android phone and wanted to do something to it. So I googled about things/projects/fun stuffs I can do with the phone. One of the results I got was about using Android phone to do "calculations" in return for "money"... That's how I learn about bitcoin/mining. Of course the article I read was already 1-2 year-old, and I wasn't able to do meaningful bitcoin mining with a phone then- the difficulty was only about  50-60 million...