1. Shutter speed: It controls time interval that the sensor of the camera is exposed to light
   The camera shutter acts similar to our eyelids that open and closes to let light enter the camera and capture the image. And the speed is related to the time for which the shutter will remain open exposing the light on the camera sensor.
   
2. Megapixel (MP): This is mainly the size of the image captured from a digital camera and smartphone camera
   Megapixel stands for millions of pixels and an image is made up of tiny units called pixels (1MP means one million pixels). Higher megapixel count in a camera will result in richer and bigger image.Basically, megapixel can also be termed as the resolution of the image (picture size). While higher megapixel means bigger resolution- which is the indication towards better image quality which is not always true, as pixel quality matters more than the number of pixels.
   
3. Aperture (f/stop): It is the opening of a lens' which basically controls the amount of light that can pass
   It is a hole in the camera, just like the pupil of our eyes which controls the amount of light that can pass through the lens and the camera sensor. It is represented as ‘f/1.5, f/2.4 and so on.Lower aperture value indicates the wider opening of the curtain of the hole and wider opening indicated towards more light that can pass through the camera lens and sensor.
   
4. Optical Image Stabilization (OIS): It helps in reducing the blur of the image
   Image stabilization generally prevents the images from getting blurred or capturing stable videos. This technology uses the moving lens elements and a gyroscope sensor. OIS determines the camera movements using gyroscope sensor to counter the movement by moving the lens module sideways or up and down. This feature is very useful while taking low-light shots and recording videos.One thing to keep in mind is that this mechanism can only minimize the effect and cannot completely eliminate it.
   

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