I think it means when you change the name of a file, it may come unusable only if you change the extension ie the exe, bmp, bat thingy at the end of the file name. For instance, if you change say, setup.exe to setup.cpy, you won't be able to run it. If you have a file called photo.bmp and you double click it, it will probably open in your paint or graphics program, PSP or paint or something - by changing the name to photo.*** it won't open automatically with that. I think the icons are associated with the extensions so that will change too. Hope this helps.