Located at the front of your camera, it allows specific amounts of light into the camera to create a sharper, accurate image.
For example in the left photo, there was a larger aperture used, which gives more attention to the image that is closes to the camera. It gives it a sharper focused look. Whereas the photo on the left is used with a slightly smaller aperture where the camera focuses on the whole of the image rather than one picture.
This could also be known as depth of field, which is the distance between the nearest and furthest objects giving a focused image. This can create much more eye catching images as it can make a specific object look much sharper, and giving it more of the attention than the objects around it in the background, while bringing out details within the object it is more focused on, like the tonality.
In order to change the option on your camera of the Aperture, it is visually seen as “F–“. With a scrolling option at the front of the camera as seen in the image, which allows you to have a higher or lower aperture option.