A letter of application is a doent sent with your resume to provide additional information on your skills and experience.The Job Application Letterisyour first interview. When applying for employment by mail a job application letter must accompany your resume.How to write winning Job Application Letters (Cover Letters). Writing an application letter is the first step in a series of career processes. Get the application Sample letter to send with a job application. Job Application Information: Letter of Application Writing Guidelines; Job Application LettersThe sample application letter format to follow can be modified to create your own job application letter. You can follow the same format as the sample job application