Alternative Menu item
Alternative Menu Items are used and work the same way as standard menu items. Since they are already based on customised layouts, template overrides do not apply to alternative menu items.
Sidebar
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Administrator
A user level on a Joomla site that has access to all front-end and back-end capabilities. Administrators is just below super user level.
Language Key
The name for a specific piece of language-specific text in a Joomla application.
KEY = Value: where “KEY” is a string to be translated and “Value” is the translated string. In a Joomla program, language keys are used instead of literal language strings. The actual text is substituted at runtime based on the currently active language.