Notes

ISO:

Controls sensitivity to light.

The best time to use high ISO is in the dark as for the brighter situations, lower ISO is the best.

The lower the ISO the clearer the image, better quality.

The higher the ISO the more sensitive, noisier the image. 

Shutter: 

Slow shutter speed allows more light into the camera sensor and are used for low light and night photography as for fast shutter speeds help to freeze motion.

 Shutter speed is mainly changed for photography but filming is 1/50

Aperture:

Aperture, f/stop (Fraction)

Aperture is an opening hole, space which let's light in depending how big or small the hole is. It controls how much light passes in.

The aperture controls your focus, Depth of field (D.O.F)

The lower the f/stop the bigger the hole, more light, blurry

The higher the f/stop the smaller the hole, less light, less blurry.