Taxation

Contributions: Made tax-free (adjustment to taxable income on personal tax return)
Earnings: Compound tax-free
Distributions: Taxed as ordinary income

Limits

Contribution Limit: $6,000 per year (generally, see next section for exceptions)
Income Limit: None (however, there is a limit for tax-free status of contributions - see next section)

Individuals over the age of 50 can contribute an additional $1,000 per year.
If your earned income is less than $6,000 you can only contribute up to the amount of your earned income.
If your modified adjusted gross income (MAGI) is over $65,000 ($104,000 for married filing jointly) you will not get the full tax-free status on contributions (with total phase-out at $75,000, or $124,000 for married filing jointly).
Distributions from an IRA before normal retirement age of 59 ½ incur a 10% penalty in addition to taxes.
Required minimum distributions (RMDs) begin at age 72.
You can avoid a penalty on an early distribution under one of the following circumstances