What do you mean by term Aperture?
Aperture if simply put means ‘opening’ . Related to photography it refers to the diaphragm opening inside the photographic lens which allows the light to pass through. This diaphragm regulates the amount of light that passes through the lens when the shutter is opened to click a photograph.
If you look carefully you will observe certain numbers engraved on the lens such as F/22, F/16, F/8.0, F/5.6 or so on. This is actually the ratio of focal length to the aperture which signifies the amount of light that will pass through on setting a particular number and are denoted by f thereby helping the photographer to adjust the amount of light he wants for his click.
The higher the ‘f number’ on the lens, the lesser will be the light that will pass through the shutter thus making the exposed surface darker and the lower the ‘f number’ on the lens, the more will be the light that will pass through the lens to make the photograph a little blurry regarding the farther parts of the scene.