An individual retirement account, or IRA, is a type of account men and women who meet certain eligibility requirements can open to save money for their retirement. Unlike a 401(k), a type of retirement account that is provided by an employer, an IRA must be opened by an individual. Another difference between a 401(k) and an IRA is that men and women can withdraw money from their IRAs before they reach retirement age to pay medical expenses without incurring the penalties that apply when 401(k) account holders prematurely withdraw money from these accounts. One similarity between 401(k) accounts and traditional IRAs concerns taxation. Account holders of both types of accounts do not pay taxes on their contributions to those accounts until they begin to withdraw money in retirement (prematurely withdrawing money from a 401(k) will incur taxes and fees). But men and women who open a Roth IRA pay their taxes up front, meaning they won't be paying taxes down the road when they withdraw money in retirement. Each type of IRA comes with its own set of rules and restrictions, including contribution limits and eligibility requirements based on earned income. In addition, men and women with a traditional IRA must begin to withdraw their money by the time they reach age 70.5, while those with a Roth IRA can leave their money in their accounts as long as they please.