A "rentier" is defined in the Random House Dictionary as "a person who has a fixed income, as from lands or bonds." The rentier class consists of those who essentially earn money off of investments instead of working on an hourly or daily wage. Many of the people who rent housing from rentiers -- in other words, renters -- live on another form of fixed income altogether: social security. Others work long hours at low-paying jobs. Renters often can't afford to own their apartments or homes, and, therefore, other entities -- including, increasingly, investment firms -- are financially benefiting from their need for shelter. Read more.