The initial release of the Linux kernel used MINIX as the default native filesystem, which was designed for use in the Minix kernel for educational purposes and hence had many usage limitations. As the kernel matured, kernel developers built a new native filesystem for disk management called the extended filesystem. The design of ext was heavily influenced by the standard Unix filesystem UFS. Due to various implementation limitations and lack of efficiency, the original ext was short lived and was soon replaced by an improved, stable, and efficient version named second extended filesystem (Ext2). The Ext2 filesystem continued to be the default native filesystem for quite a long period of time (until 2001, with the 2.4.15 release of the Linux kernel).

Later, rapid evolution in disk storage technologies led to a massive increase in storage capacity and efficiency of storage hardware. To exploit features provided by storage hardware, the kernel community evolved forks of ext2 with appropriate design improvements and added features that are best suitable for a specific class of storage. Current versions of the Linux kernel contain three versions of extended filesystems, called Ext2, Ext3, and Ext4.