A package are files and directories grouped in a single entity.

A cluster is a logical collection of packages.

A Software group is a grouping of Packages and Clusters, these are selected in the installation, and individual packages can be uninstalled from a Software Group.

Now, which is the relation between Software Groups and their Cluster Name ?

This are the Software Groups that can be selected while installing:

Group Name Package Name Required
Reduced Network Support SUNWCrnet 2.0 G
Core System Support SUNWCreq 2.0 G
End User SUNWCuser 5.0 G
Developer SUNWCprog 6.0 G
Entire Solaris Software Group SUNWCall 6.5 G
Entire Solaris Software Group+OEM SUNWCXall 6.7 G