Owning property can earn you passive income for decades to come. Once you purchase a duplex, home, or apartment building as a rental property, you’ll earn a consistent monthly income with little work. Rent should cover your mortgage, taxes, repairs, and other expenses. You’ll continue to earn income by paying off your mortgage with the rent money and saving excess rental income.

Online courses have exploded in the past five years. Experts and creators can now create video courses to teach others their craft. A course can be about anything that people want to learn. Friends of mine have created courses and say the amount of effort is similar to writing a book. But once its done and starts to sell, it’s a solid passive income stream.

Active income, on the other hand, involves earning money in exchange for a service. It could be a salary, an hourly wage, commissions, or tips. It’s essentially a trade of your time for a fixed dollar amount. Most people choose to live this way, and there’s nothing inherently wrong with that, as long as you understand that there will be a limit to how much money you can realistically earn.
Managerial accounting defines residual income in a corporate setting as the amount of leftover operating profit after all costs of capital used to generate the revenues have been paid. It is also considered the company's net operating income or the amount of profit that exceed its required rate of return. Residual income is normally used to assess the performance of a capital investment, team, department or business unit.