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.
A Note About Email Business Letters. It might be tempting to leave out the closing when you're communicating by email, but don't give in to that temptation. Although no_closing emails are perfectly fine for everyday communication with your friends and teammates, they'll seem brusque – or worse, unprofessional – to people you don't know as well. You should also use a business letter closing when you're corresponding with someone professionally about an important issue, whether it's a new project or a job opportunity.