Discord - Free voice and text chat for gamers. As you can see from the link Discord is an app that it's designed to provide voice and text chat for free. Initially Discord was built for gamers, and have some features that are intended to make it comfortable for gamers to use the app.
See return on investment. return on investment (ROI) A generic term to define a number of analytical tools for measuring the financial benefits of an investment, including cash-on-cash, internal rate of return, equity dividend,and financial management rate of return.
(A return on investment is the money a person earns from their investment, for instance a share of stock purchased for $100 dollars and sold for $200 offers a 100% ($100) ROI.) The ROI you use can be the one you expect from the business or one from another investment you may pursue in lieu of the business.