A cover letter is a letter prepared and sent by someone who wants to work in an office, agency or company specific. Job application letter including a letter or official duty. Therefore, there are certain rules that must be considered in writing.

Job seekers frequently send a cover letter along with their CV or employment application as a way of introducing themselves to potential employers and explaining their suitability for the desired position. Employers may look for individualized and thoughtfully written cover letters as one method of screening out applicants who are not sufficiently interested in their position or who lack necessary basic skills. Cover letters are typically divided into three categories:

- The application letter or invited cover letter which responds to a known job opening
- The prospecting letter or uninvited cover letter which inquires about possible positions
- The networking letter which requests information and assistance in the sender’s job search