How this works is that the designers of this camera have engineered a lens that has an extremely long field of focus which may be from a couple of feet to infinity. As long as you know the range of focus, all you have to do is make sure that you don't try and photograph something closer or else it will be out of focus. As far as things that are more distant, you don't have to worry because you really can't focus beyond infinity. But designing a lens that has the capability to be in focus from a couple of feet to infinity demands a lot of the lens designer. There are sacrifices in image quality that must be compromised to reach such a flexible depth of field.
Autofocus cameras are a solution to the problem.
Newer computer electronics available in our newer cameras allow us to happily take pictures without a thought given to focus. The camera will do it for us. Now we can have a higher quality variable focus lens in our camera without the bother of manually focusing. And the quality of our pictures will be higher for the images will be clearer and sharper. With fixed focus and probably autofocus cameras as well, you may not have the ability to work the depth of field to your advantage.