An effective cover letter is as important in the job search as an effective resume. It serves as an introduction to your resume, and no resume should be sent without one. Studies indicate that your cover letter has the life expectancy of about thirty seconds, so it must be brief, informative, and hold the reader's attention.
Employers often use cover letters as the initial screening tool in deciding whom to interview.
Where the resume is the selling tool, the cover letter or letter of application is designed with the goal of obtaining an interview. The cover letter allows you to expand on the resume and personalize your approach. A good cover letter expresses that you are seeking a more personal conversation about possible employment. It should draw a connection between the needs of the current job opening and the skills you can bring to the job. Cover letters are intended to summarize, mention particular points, provide additional information, and ask for an interview.