I run several online businesses now (all it takes to start one is a domain, hosting, and maybe incorporation). There are two notable ones. The first is meal plan membership site called $5 Meal Plan that I co-founded with Erin Chase of $5 Dinners. The second is the umbrella of blogs I run, including this one and Scotch Addict. They pay me ordinary income as well as qualified distributions since I'm a partner.
I would throw in some caution here: if your spouse works at the same company, or in the same industry as you, you are not diversified, and should something happen, you could be in a world of hurt.  Companies do go out of business, companies do lay employees off.  There is nothing wrong with working together, but realize that you are not diversified and you should be trying to maximize other income streams as a result.
India's infrastructure and transport sector contributes about 5% of its GDP. India has a road network of over 5,472,144 kilometres (3,400,233 mi) as of 31 March 2015, the third-largest road network in the world behind United States and China. At 1.66 km of roads per square kilometre of land (2.68 miles per square mile), the quantitative density of India's road network is higher than that of Japan (0.91) and the United States (0.67), and far higher than that of China (0.46), Brazil (0.18) or Russia (0.08).[234] Qualitatively, India's roads are a mix of modern highways and narrow, unpaved roads, and are being improved.[235] As of 31 March 2015, 61.05% of Indian roads were paved.[234] India has the lowest kilometre-lane road density per 100,000 people among G-27 countries, leading to traffic congestion. It is upgrading its infrastructure. As of May 2014, India had completed over 22,600 kilometres (14,000 mi) of 4- or 6-lane highways, connecting most of its major manufacturing, commercial and cultural centres.[236] India's road infrastructure carries 60% of freight and 87% of passenger traffic.[237]
"You know what they say: 'Don't work for your money. Make your money work for you,'" Jenna Goudreau, Managing Editor of Make It, CNBC's new site focusing on all things money, tells Bustle. "That's exactly the goal with passive income: By being smart about the resources you already have, an initial investment of effort can eventually earn you money while you sleep."
For a person working for a wage, their source of income is their job, or their labor (aka their time that they sell to someone). But you can own a house, and rent it out, and when your renters pay you renter every month, the source of that income check is your rental property, or your house. It would just be called rental income. If you have money in the bank in an account that pays interest, those interest payments are another source of income. We can say the source is interest payments, or we can identify the asset that is generating rent, and say your money in the bank that is generating “rent” (aka interest) is your source of income.