Updating file and e file
One prime example is the HTMLZ file extension used for Zipped HTML e Book files.
There are HTML files In this example, you'd need a specific HTMLZ file viewer like Calibre.
Or, since this file format is actually an archive, you could open it with a file decompressor like 7-Zip, after which you could open any individual HTML files with a web browser or any of the other HTML viewers/editors mentioned above.
By providing our software exclusively online, we are able to limit distribution cost and pass those savings on to E-file users.
Many programs exist that are designed to make editing and creating HTM/HTML files easy.