Digital noise is something that commonly happens when taking pictures with a digital camera. Digital noise causes an image to look grainy with small pixilated boxes of color that take away from the sharpness and brightness of an image. There are a lot of causes for noise in images, including not taking pictures with the right settings turned on, the lighting, and various other environmental factors. Luckily, you have some options with noise reduction not just in your image editing program, but with taking the pictures and even selecting the right camera.
Reduction to noise will be beneficial to you, since noise tends to make that grainy, less detailed image come through. Maybe even having a better camera could improve this, it does sometimes come down to the pixels that the equipment aquires.