I started a photography class (though it's through homeschooling). Today it was about the Aperture. Simplest way to sum it up is that the smaller the f-stop (Ex. f/5.6) the more blurry the background, the bigger the f-stop (Ex. f/22) the more focused on everything including the background.
This was a flower we brought in from outside. We used f/5.6. You can really tell that the main focus is on the flower and not the stem on the other flowers on the top.
In this picture we used f/22. It is focused more on the entire frame than of just the flower in the center.