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It's a method of exporting not only the loaded transformation or job, but all used sub-transformations and sub-jobs.

See also the concept: Lifecycle Managementdisplay/EAI/Lifecycle+Management

What does it do?

It encapsulates the ETL metadata in such a way that it is runnable from inside a zip file.  That means that the source of the jobs or transformations is irrelevant.  It can be coming from a repository, from a local file, from a remote website, etc.  The end result is comprised of the following:

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