Generally, a resume is much shorter in length compared to a CV, usually limited to one page. It is meant to be a very brief synopsis of your career and education history. Resumes should focus on measurable accomplishments rather than soft skills or listed responsibilities. Like a CV, resumes need to be updated, but those updates should be made form specific job to which you are applying.
One of the biggest mistakes you can make when applying to jobs is sending the same generic resume out for each one. Sure, you can apply to more jobs if you don’t take the time to personalize your resume each time, but chances are you won’t get interviews from any of them. If you take the time to tailor your resume, even though you’ll be applying for fewer jobs, you’ll get more interviews.