One of the quirks about the Roth IRA is that you can access the funds that you contribute at any time unless the funds were part of a conversion. Unlike a pre-tax account, the money you contribute to a Roth has already been taxed, so the IRS will not tax you on those funds if you withdraw them.
Once you withdraw more than the amount that you have contributed, your withdrawal may be subject to taxes and penalties. Use this flowchart as a guide to determine the potential tax implications of a withdrawal from your Roth IRA.