Which resume type should you use for your job search? That depends on what you are trying to accomplish. The goal of any resume is to show a hiring manager the applicants strengths, skills, and experience in as short a time as possible. According to one study, recruiters spend as little as six seconds reviewing a resume before moving on to the next, so it is in your best interests to put your finest qualities and accomplishments in a prominent position on the page.
In the United States, a CV is almost exclusively limited to professions in academia, science and medicine. In the case of academia, the main focus of the CV should be to identify yourself as a scholar. The added length, should be filled with proof of your skills as a teacher, scholar, and your knowledge of education. A CV should be thought of as a living document, and it will change frequently based on the updates in your education and career.