The basic structure of a formal letter: The rules might be arbitrary, but taken together they create a formula that produces clarity. When a letter follows all the rules, the reader doesn’t have to struggle to figure out where a piece of information might be, what action they should take next, or who sent it _ everything can be found in its place. Knowing the rules of letter writing is, in that sense, akin to knowing the rules of page layout or web design _ the format of the document should support and clarify the content.
Parts of Business Letter. A business letter will be more impressive if proper attention is given to each and every part of the business letter. There are 12 Parts of Business Letter. The Heading or Letterhead,Date, Reference, The Inside Address, Subject, Greeting, Body Paragraphs, Complimentary Close, Signature and Writer’s Identification, Enclosures , Copy Circulation, PostScript