Guidelines for Names and Titles: The salutation should typically use the person's last name, along with a "Mr." or "Ms." In general, avoid using "Mrs." or "Miss" unless you are certain of how the woman wants to be addressed. When in doubt, default to using "Ms."
Application letters and cover letters. Many people believe that application letters and cover letters are essentially the same. For purposes of this handout, though, these kinds of letters are different. The letter of application is a sales letter in which you market your skills, abilities, and knowledge. A cover letter, on the other hand, is primarily a document of transmittal. It identifies an item being sent, the person to whom it is being sent, and the reason for its being sent, and provides a permanent record of the transmittal for both the writer and the reader.