Photos that have high resolution and high bit depth are very big computer files. Bigger files take up more space and take longer to transmit. (Sending big files can even use up someone’s phone data plan for the month.)

Because resources are limited, people choose a resolution and bit depth based on what they need to see in a photo. For example, these are X-rays of a person’s broken arm and the titanium implant used to fix it. A doctor needs to look at the images for evidence of potential complications during healing. Look carefully at the details in each photo.