What is a local help server?
From Joomla! Documentation
A local Joomla! help server provides the same (or similar) help screens as the default help server at help.joomla.org. There are many reasons why you might want to set up a local help server. For example, you might want to
- serve help screens from a server on your local intranet instead of help.joomla.org.
- customise the appearance of the help screens, for example, by adding a corporate logo or using a template that matches your own site style.
- use the English help screens as a starting point for a translation of the help screens into another language.
The disadvantage to running your own local help server is that you will have to remember to update the help screens occasionally and you will have to maintain and secure an additional site.