Package, as the name suggests, packages modules of related objects. It is a building block of any SAP Project. The related objects are modularized based on chosen factors like Process, Business Area, RICEFW ID, Development Team etc. The choice of seggregation varies from project to project and usually is maintained with consistency.
SAP allows nesting of packages and hence, form a hierarchy. This helps in organizing the objects in a more sophisticated manner. It helps in moving transports in bulk where different teams working on same system are involved.
Consider application area FI. An application level package for custom objects can be defined as ZFI. In FI, there is a module RAR. A module level package for RAR can be created with name ZFI_RAR. ZFI is superpackage for ZFI_RAR. In module RAR, RICEFW FI123 related objects can be captured in package ZFI123. ZFI_RAR is superpackage for ZFI123. Now, if only RICEF related objects needs to be migrated, only package ZFI123 can be taken into consideration. For module level decision, ZFI_RAR can be chosen. At application level, whole package ZFI can be migrated.
Packages can be smartly used in projects with larger volume of Business Processes and complex team structures. Go-live and post Go-live support can be easier with better package level planning.