Hi,
First of all, it's Copyright. In Word if you press Alt0169 it will create the Copyright symbol (on iPad so can't show it!). You can then adjust the size and font (I think) and then put it over your picture as a layer in PS. Alternatively, if you want to publish your pictures to web use a free program called VSO Image Resizer (not sure if Mac compatible though) or maybe someone else can suggest a Mac program.
Hope this helps.