"Application" vs. "Resume" - What is the Difference?

Question:

It seems that every job I interview for has me fill out an application. Why does an employer want an application when they have my resume?

Answer:

Companies keep the applications on file. The applications are legal documents that require the applicant's signature. For example, the application will ask if you have served any jail time in the past.  This is something that is not on your resume, however will need to be entered onto a job application.  The job application obtains information that you may have left off of your resume intentionally however is required, sometimes for legal reasons.

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