Is there a difference between a 401k with my employer and a traditional or a Roth IRA

There are both differences and similarities.

A 401-K and traditional IRA get a deduction when you put money in, but are taxed on 100% of everything that you take out.

A ROTH IRA does NOT get a deduction when you put it in, buit after 5 years, and over the age of 59 1/2 it will not be taxed again.

The 401-k, IRA and ROTH IRA all have different funding guidelines and restrictions; however, when done properly, a 401-K can be rolled into either of the other two.  Since the 401-K wasn't taxed in the beginning it can be rolled directly into a traditional IRA, but you will have to pay taxes on it if you roll it into a ROTH.