May I use Google Earth even without internet?
YES: Without internet Google Earth cannot load new maps, but the former visited maps stay in the computer. Google Earth remembers images and maps once shown in the screen in its so called Cache memory. This cache is stored to the local disk and therefore also available without internet connection. Therefore it is also called offline memory.
As long as this cache is'nt full all recently overflown areas are still available.

And exactly thit is the problem! When the cache is full it overwrites the oldest data by newer ones. Nobody knows when the cache is full and less which data are automatically overwritten.
If I need a specific area after weeks for a presentation wihout internet these data are lost. There's only a fuzzy background without details. Google Earth has overwitten exactly this area cause someone has prepared his holiday trip on the same computer.
All the worse if you wanted to use Google Earth with GPS out of home and the necessary maps have disapeared.
Google Earth itself provides no oppotunity to backup its cache data or to transfer it to another computer.

At this point apply Cache for Google Earth!
Backup your cache with precisely that maps you need for later use.
Stay informed about the filling level of the cache.
Exchange prepared cache copies with other computers.

Features:
Management of copies of the Google Earth Cache,
Save an arbitrary number of copies of the Offline-Cache of Google Earth,
Define exact start with New project,
Activate desired offline map stocks,
Full control of the state of the current cache,
Graphical overview of filling state and date/time of last modification,
Start and close Google Earth directly from the Cache-Manager's interface

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