A letter of application is a sales letter in which you are both salesperson and product, for the purpose of an application is to attract an employer`s attention and persuade him or her to grant you an interview To do this, the letter presents what you can offer the employer, rather than what you want from the job. Like a resume, the letter of application is a sample of your work; and it is, as well, an opportunity to demonstrate, not just talk about, your skills and personality. If it is written with flair and understanding and prepared with professional care, it is likely to hit its mark.