A resume is typically sent with a cover letter, which is a document that provides additional information on your skills and experience in letter form. A resume is a concise, often bulleted summary, while a cover letter highlights and expands on certain traits or accomplishments that would be unique or ideal assets for the particular job.
In the short term, you should tweak your resume based on each job you apply to. For example, if one position you’re applying to seems to weigh a certain responsibility or focus over another, you should be sure your resume conveys your expertise in this area. At the same time, you should be updating your resume with your experience as it develops, adding any new skills you’ve learned, courses you’ve taken or awards you won.