When we perform a [b]transformation [/b]on an object, every point in the original object gets a partner point in the second object. [br][br]The original object we call the [b]pre-image[/b].[br]The new object we call the [b]image[/b].[br][br]To help us know which points are partners we use very similar names. We use a capital letter for the point in the pre-image and the SAME capital letter with a [b]' [/b]mark for the point in the image. [br][br]For example if [b]A[/b] ([i]read as "point A") [/i]is in the pre-image, then [b]A' [/b][i](read as "point A prime") [/i]will be its partner in the image.