Menu management is used to manage your website pages (insert, update, delete). By default there are two menus: "top" and "left". If you will add new zone with associated module: standard / content management, it will be automatically added to menu management.

In some cases you might need to disable some zones from menu management. Or add them if they were not added automatically. A list of associated zones is accessible like this:

Developer -> Modules Config -> Menu management -> Options -> Associated zones

Write zone names that need to be edited in menu management.

Before adding new entry to the list of associated zones, you need to create that zone.