Noob's curious abt ISO

[SATA-N]

Why does the photo look all white when I change the ISO setting??

[Teradore]

so the ISO is what changes the sensitivity of the camera's sensor (the thing that reads the light that goes in to the camera) and the more sensitive it is, the more light it picks up. making it super bright. 

[brandishwar]

ISO is one part of the "exposure triangle". If you change the ISO, you need to change the shutter speed and/or aperture to compensate. So if you go from ISO 100 to 400, which makes the sensor 4x as sensitive to light, you need to either drop your shutter speed by 1/4th (going from 1/1000 to 1/250, for example) or drop your aperture by 4 stops, or some combination therein.

[ThePointblank]

See this video on the exposure triangle, and the relationship between shutter speed, aperture, ISO and light: