DTX - Documented LaTeX File is a file extension that can be created in a format called DOCTex. It includes sources and documentation within the same exact file. They are also both user manuals and both have components installed. You can use this extension to distribute LaTex packages as well. They also come along with a corresponding .INS installer file. This file then extracts content into various files that are not together. After you have got the file extension downloaded, you will be able to run the INS file in your Latex program if you want to bring some of the files out to your system. It is very easy to install and everything will begin working as soon as you install it.