Do I have to have two rings, an engagement and wedding band?

Do I have to have two rings, an engagement and wedding band?

So my boyfriend and I want to get engaged soon, so we’ve been talking about everything that comes with that idea. Anyway I personally don’t like the look of wearing a band and an engagement ring together. I also feel it’s not cost efficient for us right now in our lives and I can always get a band later on in life. Is this weird? I just don’t see why I have to have two rings. I’m a simple woman with simple taste. A lot of people think this isn’t traditional, but no one has given me a reason as to why you need two rings.

source: http://answers.yahoo.com/question/?qid=20101006160535AAOxwSd