A PDS or Partitioned Data Set is a dataset containing

multiple members, each of which holds a separate sub-data

set, similar to a directory in other types of file systems.

This type of dataset is often used to hold executable

programs (load modules), source program libraries

(especially Assembler macro definitions). A PDS is most

somewhat analogous to a Zip file on microcomputers, except

the files stored in a PDS are not compressed.

The Partitioned Data Set can only allocate on a single

volume with the maximum size of 65536 tracks.

Besides members, a PDS consists also of their directory.

Each member can be accessed directly using the directory

structure. Once a member is located, the data stored in

that member is handled in the same manner as a PS

(sequential) data set.