The best illustration for this principle is a residential property investment: you renovate a multi-family residence, then collect rent every month. Royalties from creative works (books, films, music recordings) are also a form of residual income. Finally, entrepreneurship comes with a host of residual income-generating opportunities. Say you take after Richard Branson, create 400 companies assign a CEO to each, then let the dollars roll in. Or you create a co-op with professionals in your field, who leverage their results by compensating you for your initial investment in them. Finally, the online world is chockfull of residual income opportunities—but more on that in a separate section below.

Establishing residual income allows you to accumulate wealth faster, have a more flexible lifestyle and maintain a diverse financial portfolio. As with any successful investment, hard work is required. With residual income, however, that work tends to be upfront. Once your revenue stream is established, the work and time involved is significantly lower than active income sources. With residual income, you’ll secure funds for your future, have a better idea of where you stand financially and enjoy peace of mind knowing you’re maintaining lucrative, long-term investments.  

Or you could do joint ventures/strategic alliances for your business or for other businesses and make residual cash flow for $0 investment.. that’s what I do lol. No money, no risk, little time, 20+ years working from home. Just connect companies and take a %, use the Internet to do it locally or globally, be the intermediary & connect companies…. ;-)
There are three main categories of income: active income, passive income and portfolio income. Passive income has been a relatively loosely used term in recent years. Colloquially, it’s been used to define money being earned regularly with little or no effort on the part of the person receiving it. Popular types of passive income include real estate, peer-to-peer (P2P) lending and dividend stocks. Proponents of earning passive income tend to be boosters of a work-from-home and be-your-own-boss professional lifestyle. The type of earnings people usually associate with this are gains on stocks, interest, retirement pay, lottery winnings, online work and capital gains. 
Betterment – Betterment was the first robo-advisor to launch, almost ten years ago. They’ve automated the entire investing process, so all you have to do is watch your portfolio of assets grow (over the long run, of course). They do charge a .25% annual fee of your account total, so if you’ve got $100,000 that’s being managed by Betterment, you’ll pay just over $20 per month.
Dividend investing is right up there for sure. You don’t have to charge $48. You can charge <$10 to boost sales. The internet has enabled so many creatives to publish their works at a low cost. People will surprise themselves if they try to create like when they were in school. The other reason why I have Creating Products edging out dividends is because of the much higher POTENTIAL to make a lot more money. For example, $20,000 a year in book sales requires $570,000 in dividend investments to replicate the same amount. Plus, there is capital risk. With book sales, there is a correlation with EFFORT, and you are not beholden to the whims of the markets.

However, residual income typically has an expiration date, especially if it is being earned through a business. Effort must be continuously put into the business in order for someone to continue to receive residual income. Businesses must continue to market themselves in order to remain relevant. The best way to look at residual income in this sense is that it is a part-time job that earns full-time income.
Speaking from our own experience, you can’t be a passive McDonald’s franchisee. Every McDonald’s potential franchisee will need to complete at least thousands of hours of training before he/she would be approved to acquire a franchise and only if he/she has the financial resources to acquire a franchise. It could take years before one would get a single store franchise. Until the franchisee eventually has acquired multiple stores and established his/her own management team, the franchisee would have to put his/her nose to the grindstone and work his/her ass off every day. I won’t call it a passive investment by any stretch of imagination.

Advertising tools. Check out Google’s AdWords Keyword Tool and plug in some of the keywords that describe your niche(s) of choice. If their average CPC is more often than not over $1, chances are there might be some money to this endeavor—especially if some are over $5. Make sure to also have a look at the competition, to see how easy it would be to rank for those keywords. Pro tip: the higher the competition, the lower your odds.
My favorite type of semi-passive income was rental property because it was a tangible asset that provided reliable income. As I grew older, my interest in rental property waned because I no longer had the patience and time to deal with maintenance issues and tenants. Online real estate became more attractive, along with tax-free municipal-bond income once rates started to rise.
Residual income is money that is earned on a recurring basis, typically as the result of a single original action. Rather than earning an hourly wage, residual income is typically generated through an initial investment of time or money with the goal of earning continuous payments. Once the initial investment, product, or service is made, the ongoing income that is earned is generally passive in nature.