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.
Like other cash flow metrics (NPV, IRR, and payback) ROI takes an Investment view of the cash flow stream that follows from an action. Each of these metrics compares likely returns to likely costs in a unique way and, as a result, each metric carries a unique message about the cash flow stream.