Depth of field is one of those things that seems simple at the outset, and gets progressively more complex the more you learn. But learning about it, even at the basic level, will make a huge transformation in your work.
For instance, without first learning about depth of field, you might think that to get some background blur in your image, you just need to decrease your aperture value.
But you didn’t take the focal length, subject to background distance, and camera to subject distance into account. And with a certain combination of factors. your aperture might actually have very little to no affect on your depth of field. It’s true. Sometimes there’s no discernible depth of field difference between f/1.4 and f/11.
Once you start to understand how all of these interact, you can start to get impressive background blur, even with a point and shoot camera at a high aperture, just by knowing exactly how to control all the variables.