A resume is a concise document that summarizes your background, and is tailored to your purpose, which could be to seek an internship, a post-graduation job, admission to graduate school, etc. Your resume is just one element in your process of applying for jobs or grad school; along with your cover letter it is a critical tool as employers screen applicants for interviews.
A curriculum vitae (definition and singular and plural forms on Merrian-Webster) is a document that gives much more detail (than does a resume) about your academic and professional accomplishments. Also referred to as a CV, it is most often used for academic or research positions, whereas resumes are the preferred documents in business and industry.
