EXT1

EXT1, short for Extended File System 1, is an early iteration in the Linux ext family of file systems. It emerged in the early development of Linux storage software as a successor to the original extended file system, aiming to improve scalability and compatibility with the growing needs of Linux users.

In terms of design, EXT1 provided the basic concepts of inodes, directories, and a hierarchical organization of data. It represented an important step in moving beyond the capabilities of the original ext, but it did not incorporate some of the more advanced reliability and scalability features that would be added in later successors. The codebase was relatively short-lived in active use as the Linux filesystem landscape evolved, and it was eventually superseded by ext2.

EXT1 is therefore primarily of historical interest. It is cited in discussions of the early evolution of the Linux filesystem family, illustrating a transitional stage between the earliest extended filesystem and the more feature-rich ext2 that followed. Modern Linux systems rely on ext2, ext3, or ext4, along with other contemporary filesystems such as XFS and Btrfs. As a historical reference, EXT1 helps explain how filesystem design decisions in the 1990s shaped subsequent developments in Linux storage.