The software code areas are segments of either real or virtual memory used to store Oracle’s executable code. These areas are typically in a protected location, separate and distinct from any code being executed by the user (client) process. Software code areas are normally loaded at the first instance startup on the host machine, and are loaded as sharable, read-only code whenever possible. For example, a Unix machine running two Oracle instances loads only a single copy of the Oracle server code into memory, even though each instance will have its own set of processes and other memory structures.