The document discusses the Sales and Distribution (SD) module in SAP R3. It describes the seven key functions of the SD module: SD-MD for master data, SD-CAS for sales support, SD-SLS for sales, SD-SHP for shipping, SD-BIL for billing, SAP EDI for electronic data interchange, and SD-IS for sales and distribution information systems. Each function is involved in a different step of processing sales transactions, managing master records, supporting sales analyses, arranging deliveries, creating bills, electronic communication, and providing sales insights.