Thanks for asking. gives a good summary of the definition I use. But in brief, it’s income that isn’t proportional to the time you physically put into acquiring it. It doesn’t mean it’s not without work or effort. It’s just that most of the work is done up front and it continues to pay off long after that initial effort. Real estate fits into that box. There’s definitely a spectrum but compared to what we do as doctors, where our compensation is directly linked to our time, most of these things are quite passive.
For example, you might take photos and have them available for a fee at sites such as or Similarly, you can create and upload designs at sites such as and, where people can buy them imprinted on shirts, mugs, and so on. Similarly, if you write an e-book (which can be as short as 6,000 or so words), you might find that people are interested in buying it, perhaps via's direct publishing service.
Viral content usually has a well-designed viral strategy behind it, it is, in part, also due to luck, but creativity and preparation are also extremely important… for this reason, to get to know this world a little better, I would like to tell you today what the definition of this concept actually is, how a viral campaign works, the advantages or viral marketing and show you our favorite examples.