[X4U] Why do some images not go through on Apple Mail?

[M.Milligan]

Hi all:

My friends who have Mac and PC's tell me that some of the images I  
forward to them do not come through. For example, a person will send  
me a humourous picture or picture via email. Some of them I want to  
share with my friends. For reasons I don't understand, any text  
associated with the picture will go through to my recipients, but the  
images do not.

Can you tell me what if anything I can do?

I thank you.

Murray