3. The bigger the aperture, the more light is allowed in while the smaller the aperture, the less light is allowed in.

4. Apertures are notated as f/stops

8. The wider the aperture, the narrower the depth of field which will give you a blurrier background

9. The narrower the aperture, the greater the depth of field which will put more of your background in focus

11. When you want to blur your background

12. Use for portraits, flowers or anything else that you might want a blurred background f/5.6

14. When you want everything in your photograph sharp and in focus

15. Use for landscapes, group photos and any other photos you might want the entire photo to be in focus

16. Good example of using the wrong aperture f/4

19. Nikon and other cameras is A for Aperture Priority