What are the most important things every cover letter should have?

- Why writing

- Why you

- Why they

Your name, address information, phone and email ....

for which job you applying on which website and if Ref# is available enter it too.....

Brief description why you are the best suited person for the job .. and conclusion thanking the person in advance ...

Cover letter is just a value addition of your CV. In most cases the HR just prints the CV and sends it to the recruiting head and thus the cover letters are mostly left unread by the head recruiter and is mostly limited to the notice of the junior staff in the HR.

But in case you need to write a good cover letter make sure that it is brief and the tone of the letter should state your keenness to join the organization and your candidature would add value to the company.

Also make sure you write down your contact details clearly so that you can be contacted easily if selected. 

Tell readers:

1. Why you are writing (the opening paragraph)
2. Why they should be interested in you (the body of the letter)
3. What action needs to be taken next (the conclusion)