A profile is a short introduction to your CV, whereas a cover letter is a one-page letter going into much more detail about why you are suitable for a specific job and organisation. There will inevitably be some overlap in content, so try to write any similar content using different words (use a thesaurus) and from a slightly different perspective.

Because your profile will be on all your CVs, you normally just mention the particular job sector you are applying for jobs in (e.g. banking). A cover letter is normally used to apply for a specific advertised vacancy and so will focus on a particular job (e.g. editorial assistant in Channels TV). Sometimes you may send out a speculative cover letter with your CV and here the focus will be broad, just like in the profile, as you don't know which jobs might be available.

CONTENTS OF A COVER LETTER
State the JOB you’re applying for e.g. editorial assistant.
Where you found out about it (advert in The Guardian newspaper etc. - organisations like to know which of their advertising sources are being successful)
When you're available to start work (and end if it's a placement)
Why you're interested in that type of work
Why the company attracts you (if it's a small company say you prefer to work for a small friendly organisation!)
Summarise your strengths and how they might be an advantage to the organisation.
Relate your skills to the job.
Mention any dates that you won't be available for interview
Thank the employer and say you look forward to hearing from them soon.

Avoid Buzzwords!
Buzzwords make you sound like just another faceless candidate, a plastic applicant with no real personality who just cuts and pastes from other people's CVs. What I mean are words like; Extensive experience, Motivated, Results-oriented, Dynamic, Proven track record, Fast-paced, Entrepreneurial (What the heck do you know about entrepreneurship? If you have knowledge on this, you won't be searching for a job - FACT!)

Words like those above makes your cover letter look vague and don't really lay emphasis on your person and personal attributes. Don't tell me you are result oriented, tell me that special uncommon skill you possess that makes you achieve results.

Hope am making sense to someone. Cheers.

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