Folders
The actual storage structure depends on which driver each storage is based on. When using the local file system driver provided by the TYPO3 Core, a storage will correspond to some existing folder on the local storage system (for example, on the hard drive). Other drivers may use virtual structures.
By default, a storage pointing to the fileadmin/ folder
is created automatically in every TYPO3 installation.
Processed files
Inside each storage there will be a folder named _processed_/
which contains all resized images, be they rendered in the frontend
or thumbnails from the backend. The name of this folder is not
hard-coded. It can be defined as a property of the storage.
It may even point to a different storage.
Changed in version 15.0 Feature: #110702 - Process system resource images
Before, processed images from extensions were stored in
typo3temp/.
Images that an extension or a package ships, referenced as EXT: or PKG:
system resource, are not in a storage. TYPO3 caches their processed variants in
typo3temp/, without a database record. Do not rely
on the name or location of a processed file.
Special properties in the "Access capabilities" tab of a File storage