Passive income is the Holy Grail for online marketers. It's automatic. Effortless. But, not at first. In the beginning, it's grueling. I liken this to doing the most amount of work for the least initial return. However, over time, as your passive income begins to increase, your reliance on an active income plummets. That's when the real magic starts to happen.
I’ve read stories about people setting up ad campaigns and making thousands of dollars within a matter of hours. What’s the catch?  The big one is risk.  You’re spending money to make money, so if you turn out to set up a bad ad campaign that doesn’t convert well, you can easily lose lots of money.  That’s been the primary reason I’ve stayed away from this method of making money online.  I’m not going to bother giving advice here, because as I said, this isn’t something I’ve done.  If you’re interested, you can probably find a lot of good information via Google, but watch out – as with any other internet marketing topic, most everyone is going to try to sell you something.
Portfolio income can come from multiple sources – interest/bond coupons, stock dividends, financial strategies including derivatives and capital growth.  Each offers some cash flow and some also offer potential capital gain with some risk from liquidity and volatile prices.  In this low-yield environment, many investors rely too heavily on cash flows and to pursue this are venturing further into riskier areas than they’d normally consider.