In basic physics, often in their first year of study of the subject, students meet the concept of an
image, for example when using pinhole cameras and finding the position of an image in a mirror. They
are also familiar with the term in photography and design, through software which allows image
manipulation, even ‘in-camera’ on most Smartphones. But what is meant by the term image? A good,
clear definition is not readily available in a range of textbooks I examined, nor on various physics
sites, beyond something like ‘a representation of an object’ or ‘a reproduction of an object formed
using a mirror or lens’ (or words to those effects). None of this explains why a mirror forms an
image and a piece of paper does not, or why a pinhole does, but a large hole does not. In this short
paper, these ideas are explored in an investigative way.