RoughDraft's "Publish HTML" option (in the File menu) allows you to save your work directly in HTML format for use on the Web. Conversion is not perfect, so there may be some differences in the formatting of the "web-ready" version of your document.
Fiction published on the web usually looks strange, because HTML likes to get rid of tabs (indenting of the first line of each paragraph) and to put a gap between every paragraph and its neighbour. Short paragraphs or dialogue suffer most from this formatting. RoughDraft offers you the ability to bypass these oddities by using "Book style paragraphs". If you do want gaps between paragraphs and no tabs, the "HTML style paragraphs" options allows you to do this.
Screenplays look reasonable (though not perfect) when converted, but plays fare worse: HTML doesn't offer any way of formatting a paragraph so that every line except the first is indented. Since a play requires this format for all lines of dialogue, the web version of a play is something of a compromise.