When you create a document, it contains the font available on that particular computer. If the document is opened on another computer, those fonts may not be available. Letters appear differently, and document formatting can be affected. This is likely to happen if your design uses fonts that aren't commonly available.
The answer is to make fonts part of your original document by embedding them. They can also be converted to curves. This way, text is turned into a graphic, which is an effective method of achieving your ideal end result.
If you save the file into a raster format (jpeg, png, tiff etc.) the fonts become part of the image. Almost all of the photos found on the web and in print catalogues are raster images. As with converting to curves, it is hard to edit at a later date. However, the document will be displayed correctly.
Automatic proof checkers replace any unavailable fonts with an alternative, and will embed the new font in the proof. Check proofs carefully to make sure that you are happy with the end result. If the proof is as expected, then printing will produce good results.