What is Aperture in DSLR and what is its effect on Photography

You can select aperture mode in different cameras with different buttons.
Apperture is hole in lens which sets blurry image.
Here we will do different experiments then you will understand that what is function of aperture
F stand for aperture

If you want wide pic of group then you have to set less aperture.
F: 12
If you want picture of just single men group then you have to keep maximum aperture.
F:3