I know how aperture works but it's nice to have a visual for the different ranges. - Aperture Depth of Field Comparison
How to use aperture to get a nice blur effect. The depth of field can make a picture go from normal to amazing. Try using this to better your photos, this website has a lot more helpful information. -JPH
DSLR Manual Mode for Beginners
If you're using a DSLR & shooting in automatic, you have the worlds most expensive point & shoot camera. Check out this article!