Passive income is earnings derived from a rental property, limited partnership or other enterprise in which a person is not actively involved. As with active income, passive income is usually taxable. However, it is often treated differently by the Internal Revenue Service (IRS). Portfolio income is considered passive income by some analysts, so dividends and interest would therefore be considered passive.
Assuming you are doing pretty well and are happy with your current standard of living, what would you need to maintain your standard of living in retirement? Knowing you are on track to accumulate a nest egg to support that lifestyle is a big win. Gold medals go to those who have accumulated enough assets, or passive income streams, to be in a position to retire well.