The Front End refers to most of what is accessible to regular users. This includes browsing the forums and threads, posting messages, searching, the User CP, and anything else that regular users can access from the forum.
The 1.6 Documentation is no longer maintained and some information may be outdated.
The MyBB 1.6 series reached end of life on October 1, 2015.
This means there will be no more security or maintenance releases for these series and forums running these versions of MyBB may be at risk of unfixed security issues. All administrators are strongly encouraged to upgrade their forums to the latest release of MyBB as soon as possible.