Basically, people looking to borrow money will make a listing on the site. Those borrowers are then placed into a category and given a “rating” based on their credit history and rate. You, as an investor, will contribute money to these loans and then be paid back at the predetermined rate of interest. Invest and see those monthly interest payments deposited into your account.
Automatic investment selection is built into the platform. Investors set their criteria for the loans they want to invest in, and when one becomes available, the system invests your money for you. After that, you have 24 hours to perform due diligence on the loan. PeerStreet is the most transparent and elegant real estate crowdfunding platform I’ve used. Unfortunately, it’s for accredited investors only at this time.

Another benefit of investing in rental properties is the loan pay down. If you obtain a loan to buy the property, each month your tenants are paying off part of the loan. Once the mortgage on the property has been paid off, your cash flow will increase dramatically, allowing your mediocre investment to skyrocket into a full-fledged retirement program.
Passive income is the Holy Grail for online marketers. It's automatic. Effortless. But, not at first. In the beginning, it's grueling. I liken this to doing the most amount of work for the least initial return. However, over time, as your passive income begins to increase, your reliance on an active income plummets. That's when the real magic starts to happen.
If an investor puts $500,000 into a candy store with the agreement that the owners would pay the investor a percentage of earnings, that would be considered passive income as long as the investor does not participate in the operation of the business in any meaningful way other than placing the investment. The IRS states, however, that if the investor did help manage the company with the owners, the investor's income could be seen as active since the investor provided "material participation." 
Residual income is the best model for money generation. Once you master and build up one avenue, you can devote your time and money into another avenue. Eventually you start reaping the benefits of multiple residual income avenues. Enabling you to have complete financial and time freedom. I recommend to all people to build these types of asset models as they can greatly improve their life.