What is What is Optical image stabilization? - Definition?

Optical image stabilization definition

Optical image stabilizer (abbreviated as OIS) is a mechanism used in the camera that shifts lens in parallel to the focal plane. With the help of two gyro sensors, it detects the shakes and movements. Based on information from sensors, it stabilizes the recorded image by varying the optical path to the sensor.

Having this feature in camera improves the photography and reduce the chance of blur images or shaky videos. It is worth to note that it cannot help if blur is caused by your subject moving too fast. It only works to counter camera shake.

You will see notable difference in video recording where OIS offers smooth videos.

OIS has been around since mid-90s when it came in compact cameras and SLR lenses for allowing photographers shoot longer exposures without using a tripod. Now this is becoming an important feature in smartphones. Mostly high-end smartphones offer OIS feature.