An object is a thing or diagram or shape that can be seen.
eg A triangle is an object
eg A person is an object
An image is a thing or diagram or shape that is created after a transformation. A transformation is when a shape changes;
Remember, the main four types of transformations are:
Example
Triangle ABC has been enlarged through the centre of enlargement O by a scale factor of 3 to create Triangle A'B'C'.
Triangle ABC is the object and Triangle A'B'C' is the image.