A résumé, no matter how good, will not get you a job by itself.
However, a good résumé will attract the attention of the hiring manager and secure a job interview.
The purpose of the résumé is to disclose your accomplishments and qualifications to a potential employer. If the employer likes what he or she sees, he or she will contact you for a face-to-face meeting.
Think of your résumé as a promotional brochure about you. You need to show a potential employer what you have accomplished and where your experience lies. Your strategy should be to emphasize the experience and skills that a particular employer is looking for.
Your résumé is also an example of your communication and organizational skills. A well-done résumé is itself another reminder of what kind of valuable employee you would be. Likewise, a sloppily produced résumé is a terrific way to get yourself taken out of the running before it even starts.