A Residual income, also commonly referred to as a passive or recurring income, is an income that continues to be generated after the initial effort has been put in. You can now see why it’s considered to be the most lucrative income source, since it doesn’t require you to trade your time for your money the same way a linear income does. So how’s it possible? Well, it’s another point to team internet. Before the internet, passive or residual income was only possible through a few means whereas nowadays, the possibilities of an earning a residual income is far broader. Let’s review the pro’s and con’s of residual income below:

I actually spent a year and a half working as an affiliate marketer (mostly selling drumming related products – lessons, kits ect). 5 years on and one of my one page sites (which I’ve not touched) still nets me about $150 a month. I won’t be retiring off that but only really now appreciate the reverse pyramid approach to entrepreneurship (working for nothing initially but later being paid without effort!)

The first form of residual income, the leftover cash after bills and expenses are paid, is important when a person is growing their savings account or is seeking a loan or financing. When getting a loan, there must be an adequate amount of residual income available to ensure a person has the money to make the loan payments each month. If there is not adequate residual income, financing or loans will not likely be approved.
So as you can see from the above example, using the concept of residual income, although Company X is reporting a profit on its income statement, once its cost of equity is included in relation to its return to shareholders, it is actually economically unprofitable based on the given level of risk. This finding is the primary driver behind the use of the residual income method. A scenario where a company is profitable on an accounting basis, it may still not be a profitable venture from a shareholder's perspective if it cannot generate residual income.
Nobody gets early FI investing in bonds, CD’s, or even stocks unless they make a huge income or are extremely frugal or a combination of both. Paper assets just don’t provide enough returns. Business income can be great but it is typically not as semi-passive as I would like and there is a relatively high failure rate. That is if you can monetize an ideal to begin with. RE investing needs to be higher ranked IMO as a way that the “average guy” can become FI.
Buy a small business: A local small business, like a car wash or a laundromat, is a great way to put money down on a money-making venture. Automate it so you don't have to be on the premises unless you're collecting money. Go into a local business with your eyes wide open - study the books, especially on income and expenses, and examine water and utility bills if your venture will be open 24 hours.
Residual income is when you continue to get paid after the work is done. This includes royalties from books, movies, or songs and also income that comes from real estate or business investments where you don’t actually have to be present to earn it. For example, Bill Gates is still making a residual income from Microsoft even though he isn’t working there anymore.