Aperture or Diaphragm

Aperture or diaphragm is an umbrella term for the lens aperture. If likened to a window, then the diaphragm is kiray / gordyn that can be opened or closed to adjust the amount of light entering. Aperture on the camera is denoted by the letter F and the unit as follows:
f/1.2
f/1.4
f/1.8
f/2.0
f/2.8
f/3.5
f/4.0
etc. ...

The smaller the number of units will increase the aperture lens (f/1.4 larger opening than the f/4.0).

Thus, the correlation between shutter speed and aperture is that the larger the aperture, the shutter speed will be faster, smaller aperture on the contrary, it will be increasingly slow shutter speed.

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