D-Day

So basically, I'm not too sold on my idea which is the topic of D-Day. AS much as I would like to change it, I feel like half the battle of this research paper is picking a topic so since I have one, I'm sticking to it. With what I have found with the class exercises is that I need to focus in on one thing about "D-Day". If was a day event and a lot can happen in 24 hours. What I want to explore is, I guess a big question in itself but, why? Why did this event happen? What were the events that lead to it. In my research, I have found that the main event happen in Normandy, France in June 6, 1944 and also that But the thing is, I'm getting confused with Normandy and the Omaha Beach battle. I guess I better get my facts straight.