The database server comprises Oracle instances and databases with many features like Streams, Partitioning, Warehousing, Replication, and Real Application Clusters (RAC), but ultimately it provides a reliable, mature, robust, highperformance enterprisequality data store, built on an objectrelational database system. Historically, one of the projects undertaken in the late 1970s to animate the relational theory proposed by Dr. E.F. Codd resulted in the creation of a relational database management system (RDBMS) that later became known as the Oracle Server. The Oracle Server product is well established in the worldwide database market, and the product is central to Chapter 1: Architectural Overview of Oracle Database 11g 5 PART I Oracle Corporation’s continued growth, providing the backbone for many of its other products and offerings. This book is dedicated to describing the essential features of the Oracle Server and the primary mechanisms used to interact with it. It covers the aspects that are measured in the certification exams, but by no means explores the plethora of features available in the product.