# Oracle Parallel Server

Oracle Parallel Server is an architecture that allows multiple instances to access a shared database. Oracle Parallel Server offers the following:

- Superior scalability through distribution of workload across nodes
- High-availability through multiple nodes accessing the database; if one node fails, the database is still accessible through surviving nodes
- Each Oracle Parallel Server instance, a running instance of Oracle8i software, is comprised of a System Global Area (SGA) and Oracle background processes. The SGA is a shared memory region that contains data and control information for an instance. Users can connect to any instance to access the information that resides within the shared database.