It can be a little confusing, but essentially there are two answers: in many parts of the world, notably most of Europe, a CV (or curriculum vitae, or simply vitae) is just your resume. It’s one of those linguistic differences that probably came about decades ago—I’ll leave the research up to the etymologists out there. If you are seeking an international role, find an expert to help you, as different countries have different rules and expectations from CVs.
But the second answer is potentially more relevant to us in the US. Here, while a resume is standard for most professions, a few fields use CVs. These are things like the sciences, academia and medicine, in which lots of experience and highly specialized knowledge is important to demonstrate. In these cases, CVs are generally notably longer than resumes. (I once knew a professor had his divided into chapters.) Disciplines in which this is often have unique formats or expectations, so if you’re getting into an industry like this, you’ll need some resources at the start. It’s better to speak with others in your discipline or seek expert advice than simply to search for examples online, since those aren’t vetted by hiring professionals in the field. Sites like USAJobs or official tips from professional associations are often good places to start. If you’re in grad school, ask if your career center has dedicated specialists, or gather opinions from your faculty. (Be sure you get more than one opinion, because professors are rather famously notional individuals, and you might wind up putting too much faith in something that is simply one person’s quirk.)
For many of you, this distinction won’t matter much, but in case you’ve ever wondered, wonder no more!
