ISO Speed

ISO speed shows how sensitive the image sensor is to the amount of light present. The higher the ISO, the more sensitive is the image sensor.
The ISO is represented by numbers:
ISO 50 100 200 400 800 1600 3200

Each number represents two times the sensitivity than the previous one। Higher ISO settings are very useful in low light situations, but the disadvantage of noise appears. The higher the ISO, the higher the noise levels you get.