Upgraders

If you have used an earlier version of Joomla, the fundamentals are unchanged — articles, categories, menus, modules, components and plugins all work the way you remember. The administrator interface, however, has been rebuilt, and a number of things have moved or been retired.

The changes most likely to catch out a returning user:

• Basic Search has been removed. Smart Search is now the search component. A site carried forward from an older version may still have a menu item pointing at the old component, which will need repointing.
• Weblinks is no longer part of the core package. It is maintained as a separate extension and is installed and updated on its own.
• Custom Fields let you add your own data fields to articles, contacts and users without writing an extension.
• the core JavaScript framework has gone. Older extensions and template overrides that relied on it will need updating.
• Guided Tours in the administrator walk through common tasks step by step.

Anything that has been heavily customised — particularly template overrides and third-party extensions — should be reviewed rather than assumed to carry across. Joomla User Guide