Final answer:
A cover letter is a one-page document that introduces your resume when applying for a job.
Step-by-step explanation:
A cover letter is a one-page document that is traditionally submitted along with your resume when applying for a job. It serves as the introduction to your resume and aims to entice the prospective employer to read your resume. The cover letter should be a concise document with three or four paragraphs, each serving a specific purpose.