Fundamental to Configuration Manager's software distribution process is the use of collections to manage resources within a site. Using these collections allows you to group your clients (and other resources) together and control when and to whom software packages are distributed, based on the membership rules designated for that collection. For more information about collections, see About Collections.
To distribute a software package to clients, you must specify a collection, which is then used by Configuration Manager as a set of clients to which the program will be advertised.
Subcollections provide you with the ability to link collections together for better resource management. This can be especially useful when a particular collection of resources can be further divided into smaller units, which can then become subcollections. For more information about subcollections, see About Subcollections.