Greg Johnson is a personal finance and frugal travel expert who leveraged his online business to quit his 9-5 job, spend more time with his family, and travel the world. With his wife Holly, Greg co-owns two websites – Club Thrifty and Travel Blue Book. The couple has also co-authored a book, Zero Down Your Debt: Reclaim Your Income and Build a Life You'll Love. Find him on Instagram, Facebook, and Twitter @ClubThrifty.
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. 

Residual income is calculated as net income less a charge for the cost of capital. The charge is known as the equity charge and is calculated as the value of equity capital multiplied by the cost of equity or the required rate of return on equity. Given the opportunity cost of equity, a company can have positive net income but negative residual income.