Camera resolution refers to how many pixels a camera’s sensor contains.Pixels (short for pixel elements) are the microscopic sensors that capture the light image formed by the lens. In the same way that grains of silver capture light images with film, pixels record the light image in a digital camera. Pixels are arranged on a digital camera sensor in what is called an array or grid.Theoretically (all other things being equal), the more pixels a sensor has,the higher the camera’s resolution and the better the image quality should be. But all things are not equal among pixels and sensors. For various technical reasons (and I cover more about this in a later FAQ), a higher pixel count does not necessarily translate to better image quality.That being said, however, pixel resolution is a fairly good indicator of picture quality.
Camera resolution is stated in megapixels — 1 megapixel being a million pixels. So, in most cases, if a camera manufacturer lists the resolution of a particular camera as having 10 megapixels, it has 10 million pixels on its sensor. The actual number of pixels is measured by multiplying the number of pixels in a vertical row by the number in a horizontal row. For example, a camera that has a pixel array that measures 4,000 pixels wide by 3,000 pixels high has 12 million pixels — or 12 megapixels.