IEP vs. 504
Often times, individuals confuse an Individualized Education Program or Plan (IEP) with a 504 Plan.
Here is some information to help better understand the two:
IEP
A document that outlines the special education goals, services, and supports of a child who has been determined to have a disability and is in need of special education. This document is reviewed annually to determine if changes in services and supports are needed.
504 Plan
A plan that outlines the services and accommodations that a student with a disability receives under the law.
A more detailed description and side-by-side comparison of the two is available here: The difference between IEPs and 504 plans