It does not really make sense to create a empty file..
In most cases you will rather generate content with a software that you will want to save later.
For example, you will receive files (images, videos, documents) from your friends or family, you will import music from CDs or photos from your camera, you will want to save a text you typed in a word processing software.
In all these circumstances, the softwares
will ask you where to save what you want to save when you will get to that point. As simple as that.