NDCs are used to identify drug products in many different ways. For example, the 11-digit format is often used for billing purposes, while the 10-digit format can be used for ordering and reporting purposes. NDCs can also be used in electronic health records (EHR) systems to help track and compare medication use patterns. The NDC also serves as a key identifier when tracking pharmaceuticals across the supply chain. This helps ensure that medications are safe, effective, and properly labeled throughout their entire lifespan.