Retirement is the withdrawal from one's position or occupation or from one's active working life. A person may also semi-retire by reducing work hours or workload. Many people choose to retire when they are elderly or incapable of doing their job due to health reasons. People may also retire when they are eligible for private or public pension benefits, although some are forced to retire when bodily conditions no longer allow the person to work any longer (by illness or accident) or as a result of legislation concerning their positions. In most countries, the idea of retirement is of recent origin, being introduced during the late-nineteenth and early-twentieth centuries. Previously, low life expectancy, lack of social security and the absence of pension arrangements meant that most worker