OK My knowledge of this is very basic, so maybe someone could fill in the blanks.
IRA's are tax-sheltered accounts-meaning they're deferred from being taxed on the icome generated from it.
The buzz word in finances is a ROTH IRA which offers you the most benefits of all the IRAs. This actually offers you the benefit of NOT being taxed at all for withdrawls, as long as you're at least age 59.5 or using it for a first time home purchase,used for death/disability, and it's been in existence for at least 5 years. The contributions however are not tax deductible.
Basically its a retirement account that offers those advantages over a standard 401K or other retirement account.