n'est pas

Today I am getting a 401k. I have no clue what to invest in. Lifestyle funds? Real assets? International markets? I am thinking I want to put just a bit in international markets. Aggressive, conservative, what. And what the hell is a Roth IRA. Can anyone help me here. I have an appointment today with a financial advisor and I am going to sound like a total idiot going in.

Oh and also today is my birthday, I am 27. About damn time, right.