Cover letter should speak about your personality.it should make the employer curious to see the resume. Employer considers resume only if the cover letter is impressive, if not it may not be considered.
Cover letter should be typed only in the body of letter but not as an attachment to avoid wastage of time of interviewer or HR. if you don’t have respect for employer’s time, your application will not be considered.
Cover letter need to be brief and check for all spelling and grammar mistakes.
In the cover letter you should explain in which way you can be an asset to the company. In the cover letter you should explain how you are best fit to the company and how you can do good to the company but not how you are going to be benefitted by the company. You need to explain how passionate you are about the job because without passion for the profession neither you can get success in the company nor you can survive in the company.
Cover letter cannot be the same for all companies, it should be adjusted according to the requirement of the company.
A Cover Letter is enclosed by a resume and sometimes by an application for employment.
In cover letter you will explain how your qualification, experience and technical skills are suitable to job and how you are fit to the job.
In cover letter you will make an attempt to explain how you can do good to the company, if you are permitted to shoulder the job responsibilities.I have explained very clearly how to adjust the cover letter according the requirement of the company in my video. I also gave a sample cover letter in the video.