This introduces an applicant and the applicant’s résumé to a potential employer:

The answer is Cover Letter.
A cover letter is one- page introductory document meant for the employer to  get a glimpse of the potential candidate. It shows the candidate's overall strengths and why they would be fit for the organization. The cover letter helps the candidate stand out from a crowd and it is meant to get the employer engaged before reading the resume of the candidate. 

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