IPhone 4 screen replacement

So I'm planning on replacing my iPhone screen and to be safe I'm backing up my memory; I don't want to because it's a lengthy process

But will my phones memory be erased if I change the screen?

I recommend just going into an apple store and showing them your iPhone. It's the safest way to get your screen replaced. And your phones memory will NOT be erased, because it is just your screen that needs replacing.