Introduction
What is a fragment? As of version 2.5 there are two conent-pushing systems in uPortal, ALM or Aggregated Layout Management and DLM or Distributed Layout Management. This page refers to fragments in ALM. See DLM documentation for pushing fragments with DLM.
Types of fragments
Pushed Fragments
Pushed fragments are not removable or editable by the user. They are "pushed" when you use pushfragment in 2.3.x and pubfragments in 2.4.
The delete button will always be disabled for pushed fragments since they will be added to a user's layout no matter what. The only way to remove from a users layout is remove that user's permission to view the fragment, make the fragment pulled or delete the fragment.
Pulled Fragments
...TODO...
Managing Fragments
Beginning with the next uPortal release pushed fragments created by the pushfragment utility can be managed by admin in the fragment manager.
You may add fragments by editing the file /properties/al/fragments.xml
Fragment Priority Range
Priority is documented around page 57 of this PDF: http://www.immagic.com/uPortalDocumentation/uPortal_Documentation_Chapter_2.pdf