Contact Information: The first section of your letter should include your contact information and the contact information of the person you are writing, too. Also, include the date you are writing at the top of your letter. Letter Salutation: Unless you know the reader well and typically address them by their first name, you should include the person's personal title and full name in the salutation (i.e., "Dear Mr. James Franklin"). If you are unsure of the reader's name, include his or her title (i.e., "Dear Executive of Marketing"). If you are unsure of the reader's gender, simply state their full name and avoid the personal title (i.e., "Dear Jamie Smith"). If you are unsure of the reader's gender, name, and title, simply write, "To Whom It May Concern." Leave one line blank after the salutation.
There is a tendency to think that the often arbitrary rules of letter writing don’t really matter, that as long as your recipient can work out what you’re saying, that’s good enough. This shows a great deal of disrespect for your recipient, though, and for your own ideas. It suggests that a) your reader’s time isn’t valuable enough for you to write clearly and efficiently, and b) that you don’t particularly care about the content of your letter.