We are often asked what the best file format is for moving text between documents. Actually, text is easy. Formatting is another story.
Preserving formatting across programs and platforms is tricky. Most programs include features that can't be interpreted by other programs: custom line styles, backgrounds, complex text effects. If you're looking for portability, don't use these features. For basic character and paragraph formats, the best choices are RTF (Rich Text Format) and style tags. RTF files include information about the formatting, and can be exported from and imported into most programs. Style tags keep formatting and text completely separate. All formatting is stored in style descriptions. Style tags are applied to text to apply the styling. The style descriptions can be recreated in any program, and the text, with tags, can be exported and imported as a simple text file.