It relates to what kind of document you are going to write. It is very important to know appropriate tone of writing. Documents usually have a formal tone. This tone is used in reports, instructions and other business docs. You can't use slang, bad words etc in formal toned docs. Also your writing should to sound natural so don't make your docs stuffy.
“Life is for the strong, to be lived by the strong, and if need be, taken by the strong”
