The UMD stands for the Ultimate Messy Directory. It started on May 3, 1998 as an unliked page on a music store website, just a plain text file filled with bookmarks to messy finds on the internet. Without any advertising, suddenly hundreds of people found the bookmarks and began to submit emails with more finds.

That same year, the site was switched over to manually-maintained HTML, and a forum and chatroom were installed. The site took on the same color scheme, logo font, and general feel of the music website it was derived from, all of which persist today in Night Mode. In 1999, iWam.com (formerly messy-ABC) was launched as one of the very first sites selling membership access to messy videos, and it became the main sponsors, allowing UMD to continue to exist.

In 2000, the site was converted over to the PHP programming language and used database-based storage. Based on this, a new forum was built from scratch, along with the user profiles system. In 2009, the UMD.NET download store was launched.

UMD.NET continues to be developed on its own independent platform and codebase, which inherently sacrifices certain efficiencies but allows for the site to be constantly molded to the behaviors and wishes of its visitors, some of whom have been here and contributing for almost a quarter century.

The future of UMD.NET will see it offer a mobile-friendly version, and more options for live videos.