AP Workflow is an electronic invoice tracking and authorization process that manages the uploading of invoice images, data entry, coding to general ledger accounts, and approval process to authorize final payment to suppliers. It integrates with ERP systems and includes features like workflow diagrams, generated emails, worklists, voucher details, images, cost allocation, approval routes, and more. Implementing AP Workflow can provide benefits like ensuring invoices are approved and paid on time to receive discounts, avoiding lost invoices, and improving resource efficiency within the AP department.