IBM i5/iSeries Primer(c) Concepts and Techniques for Programmers, Administrators, and Sys[... ]ators

A library is just a container with a name. In other systems, a library is called a folder or a directory; on the i5, it is called a library.

Libraries can contain any number of objects, but they cannot contain other libraries. The only exception to this limitation is library QSYS, which is discussed later in this chapter.