An inode; Acronym for index node, refers to the fundamental data structure of the file systems of Unix-based operating systems and Linux derivatives. The identification of the inode takes place within the partition exactly via the inode number. Name entries within a directory refer exactly to this inode, which contains the metadata of the file or the file list of the directory. When saving a file, not only the usable file (file content) must be stored, but also the respective metadata. These consist among other things of the time of generation (time stamp), the owner of the file, the file type and the capacity.