┌─────────────┬──────────────┐
VOLUME 1      │    A.B.C    │   D.E.F(1)   │
              └─────────────┴──────────────┘
 
              ┌─────────────┬──────────────┐
VOLUME 2      │   D.E.F(2)  │    X.Y.Z     │
              └─────────────┴──────────────┘

A multivolume, multifile data set is a part of a collection of data sets that span two or more volumes. The name multivolume, multifile applies to the entire collection of data sets written together, whether each data set actually spans a volume boundary. In other z/OS manuals, this collection of volumes is called an aggregate.

In this example, A.B.C, D.E.F, and X.Y.Z are all multivolume, multifile data sets. A.B.C. is file 1; D.E.F is file 2, regardless of the volume; and X.Y.Z is file 3.