Wesley:
I look at IRAs by when you pay your taxes on investment. ( Be Wary, this is simplified. And, you know the IRS doesn't do simple!)
On a traditional IRA you can get a deduction on your income tax and the funds grow tax free until retirement. You will pay taxes when you pull the money out to retire. Some folks think this is a good deal because they think there taxes will be lower.
On a Roth IRA, there is no deduction upfront but you can take it out later tax free. It also grows tax free.
All IRAs are accounts for investing. Just like a 401k at work. You can put your money in stock funds, individual stocks, bonds etc
Self Directed means that you are picking your own investments ( not just putting them in a fund). You can buy a business down the street. You can buy real estate etc etc. There are a lot of rules around Self Directed Roth and investments. You can't rent a property to an immediate family member, etc. But, 20, 30 or 40 years of tax free growth is worth it to jump thru the hoops.
I hope this helps a little. ~ C
