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When the ISO value is small, the camera absorbs less light and the camera produces sharp images. So, with the low ISO value you can enjoy the effect of tracing movement of the light (i.e. stretched lights of the traffic or stars - see the 1st photo above ) with good image quality. Also it works when the sunlight is bright in the midday or early afternoon (see the 2nd photo above), as the low ISO controls the intake of the light. With the high ISO value a camera absorbs much light but compromises the image quality, resulting in noise and discoloration but you can photograph with high shutter speed in the low light. The good quality of the sensor and noise-reduction better the image quality even with the high ISO value.

Aperture (F value) decides the depth of the image (when the subject is close, shallow (2nd photo), and when the subject is in distance, deep (4th photo)) by either opening wider or closing narrower the opening of the lens. And if the range of F value is wide, you can enjoy different effects when you want to close up a nearby object and blur the background (with low F value - see the background of 2nd photo) and  when you want to realize radiated rays of sunshine (with high F value - see the 3rd photo). The good sensor quality also gives an impact on photography with high F value.

Sensor size

The sensor size is important when choosing a camera as it can improve the image quality particularly when the amount of the light intake to the camera is small (i.e. high ISO value and high F value, night, caves, cathedrals etc). With a great sensor you can take clear photos at night or in the dark indoor with lower risk of motion blur and in some cases you might not need tripods (see the 5th photo). The sensor quality is relevant to the price of the cameras.

Shutter speed

Shutter speed means how long it takes to absorb the amount of the light into the camera and also relates to depiction of the moving subjects. High shutter speed captures events (i.e. wild life and performance movements of athletes) happening in a shorter period of time to appear still in the image. Slow shutter speed depicts traces of movements i.e. automobile lights, star movements, flow of water, northern lights etc.

Resolution

Resolution decides the number of dots in an image, sharpness of the photo and how much the details are displayed there. If you want to print the photos or publish them then, resolution is vital. Image size is measured with megapixel. If this aspects of quality of camera matters then you can check "Max resolution" to choose the camera with the large value (5000X3000 or more). But resolution also represents the size of the images. If the resolution is high (and the size of the image is large) you might experience some difficulty in electronically transmitting the images. I would not recommend expending the image size to make the photos clearer (i.e. 2200 X 1700 to 5000 X 3000 ). That will cause some problems with the image quality. 

So, first three (ISO, aperture and sensor size) pretty much decides the performance of the camera, and makes it possible to take good quality photos in good or poor light conditions. If you aspire to produce professional quality photographs and see your photographs as works or/and would like to realize a wide range of photographic styles then the shutter speed range and image size would matter.

Physical size and weight of camera 

These two elements are perhaps important to many of the users that use camera outdoors or at least need to carry it.