aperture

Aperture is the opening in your camera that lets in the amount of light that you want for your image. Aperture is measured in f stops. If your aperture is f/5.6, then there is more light let into your camera (bigger hole). If your aperture is larger, for example f/10, then there is a smaller hole and less light let in. Aperture affects exposure because the more light let into your camera, the brighter your image will be. It is the same for the opposite, if you have a high aperture (small hole) then there is less light let in, and the image would be darker. This also affects your depth of field because the larger your aperture, the larger the depth of field you have

The first image's information (the leaf) is ISO 800 - 55 mm - f/5.6 - 1/100. Since the aperture is smaller and there is more light let into the camera, the image was pretty bright, so I ended up moving my ISO from 100 to 800 so that it wouldn't be so overexposed. My second photo's information (the flag pole) is ISO 100 - 18 mm - f/11 - 1/60. My aperture is now at f/11, which is a much smaller hole, and less light let in, than the f/5.6. Because of this, I put my ISO at 100 so that the image would be bright enough.