Love it or hate it, Social Security is the foundation of retirement in America, but what people don't know about the system can hurt them.
The benefits from the public pension system initiated by President Franklin Delano Roosevelt in 1935 account for more than half the retirement income of more than 75 percent of retired Americans.
For many millions of people, Social Security benefits will be their only source of income after they stop working. And with the inexorable decline of private defined-benefit pensions in America, Social Security's guaranteed income will only become more important in the future.
"Social Security has become absolutely key to the retirement of Americans," said Alicia H. Munnell, director of the Center for Retirement Research at Boston College.
"It's a source of income adjusted for inflation that keeps going for as long as you live," she said. "You want to have as much of this income as possible."