IRAs force you to start withdrawing funds at age 701/2. The amount is based on a formula involving your total account and your life expectancy. You can take more than that but face a penalty if you take less. What I found interesting is that the formula is designed to draw the account down to zero if you reach your life expectancy.
Yes, that is because the funds in the IRA were never taxed as income, and they want to be sure to get income tax on that money.
If you die and pass along the IRA to spouse/kids, it will be set up to become taxable to them, one way or another.