George Orwell gave us Animal Farm and 1984. In his 1945 essay, "Politics and the English Language," he discussed writing - and I like PickTheBrain's synopsis of Orwell's teachings to these five rules:
1. Never use a metaphor, simile, or other figure of speech which you are used to seeing in print.
2. Never use a long word when a short one will do.
3. If it is possible to cut a word out, always cut it out.
4. Never use the passive when you can use the active.
5. Never use a foreign phrase, a scientific word, or a jargon word if you can think of an ordinary English equivalent.
Robert Heinlein produced science fiction classics like Stranger in a Strange Land and Starship Troopers. His Rules of Writing are so popular, you can buy them on a tee shirt:
1. You Must Write.
2. Finish What You Start.
3. Refrain from Rewriting, Except to Editorial Order
4. You Must Put Your Story on the Market.
5. You Must Keep It On the Market Until It's Sold.
Mark Twain's 18 Rules of Writing are hilarious - and true - and while too long to list here, can be read in their entirety at the PBS site in Twain's 1895 Essay, "Fenimore Cooper's Literary Offenses." Here's an excerpt:
12. Say what he is proposing to say, not merely come near it.
13. Use the right word, not its second cousin.
14. Eschew surplusage.
15. Not omit necessary details.
16. Avoid slovenliness of form.
17. Use good grammar.
18. Employ a simple and straightforward style.
Finally, the well-known rules established by Elmore Leonard in his 1991 essay for the New York Times, "Easy on the Adverbs, Exclamation Points and Especially Hooptedoodle," which has been expanded into book form and is currently for sale on his website and elsewhere, if you're interested. They include:
1. Never open a book with weather.
2. Avoid prologues.
4. Never use a verb other than ''said'' to carry dialogue.
7. Use regional dialect, patois, sparingly.
8. Avoid detailed descriptions of characters.
11.If it sounds like writing, rewrite it.