For three years the Linux kernel had been developed with BitKeeper, a proprietary version-control tool whose maker allowed kernel developers to use it free of charge. In early 2005 that arrangement collapsed, and the kernel community suddenly needed a new way to track its source code. Rather than adopt an existing tool, Linus Torvalds decided to write one.
The work happened fast. In an April 2005 message on the Linux kernel mailing list, Torvalds wrote that he had “worked on it (and little else) for the last two days” and described the result as “a distribution and archival mechanism” rather than a conventional source-control manager. The first commit in git’s own repository, authored by Torvalds and dated April 7, 2005, is wryly titled “Initial revision of ‘git’, the information manager from hell.”
Within days the prototype was tracking its own development, and shortly afterward it was managing the Linux kernel itself. The speed was possible because Torvalds focused first on a small, fast core for storing and retrieving snapshots of a project, leaving higher-level convenience features to be built on top later.
The milestone matters because git did not stay confined to the kernel. The tool created in that two-day burst became the foundation for how most of the world’s software is now versioned, and for hosting platforms built around it.