Dateisystems

Dateisystems, or file systems, are the software components that manage how data is stored and retrieved on storage devices. They provide a hierarchical namespace for organizing files and directories, maintain metadata such as ownership, permissions, timestamps, and access control lists, and implement the methods by which applications perform operations like create, read, write, and delete. A file system must be mounted by the operating system to access its storage medium, and it may span multiple devices or volumes.

At a low level, file systems manage storage in blocks and use metadata structures such as inodes or tables to describe files. Directories map names to these entries. Some systems are inode-based (ext4, XFS, NTFS), while others use table-based metadata (FAT). Features often include copy-on-write, journaling, encryption, checksums, and snapshots for recovery.

Common examples include FAT variants for removable media, NTFS on Windows, ext4 on many Linux systems, APFS on Apple platforms, ZFS on servers with built-in volume management, and Btrfs as a scalable Linux file system. Network and distributed file systems, such as NFS and SMB, provide access over a network; parallel file systems like Lustre and GPFS are used in high-performance computing for large-scale data.

Dateisystems reflect trade-offs among performance, reliability, capacity, and compatibility. Design choices — such as journaling versus copy-on-write, metadata placement, and permission models — influence crash resilience, throughput, and maintenance tasks like filesystem checks. Ongoing developments focus on scalability, data integrity features, and integration with encryption and tiered storage.