Try this simple experiment to get an idea of how UltraDedup® compares with Zip

   (1) Create an empty directory. Let's call it TestDir.
   (2) Copy a "large" (say, about a gigabyte) compressed video file (e.g. mp4) to TestDir.
   (3) Copy the same file to TestDir but give it a different name.
   (4) Compress the contents of TestDir using Zip.
   (5) Compress the contents of TestDir using UltraDedup®.

If your video file was a gigabyte then the output of Zip would be about two gigabytes.

The output of UltraDedup® would be about one gigabyte.

Let's say you have a directory that represents the contents of your website. The website contains lots of videos and html code and databases. Let's say that that website contains five gigabytes of data.

Let's say you want to back up your five-gigabyte directory every day. Of course you could zip up the five-gigabyte directory but the zip file will likely be 5 gigabytes because videos tend not to be compressible.

Worse, if you add an identically-named file to a zip file, the file will be replaced and the old file will be lost.

UltraDedup® solves both of these problems by implementing something we call Chapters. One can think of a Chapter as a collection of files and directories at a point in time.

UltraDedup® automatically takes care of removing redundancies among Chapters. You can fetch (e.g. restore) any file or directory from any Chapter. You can fetch an entire Chapter, too.

Continuing with our five-gigabyte directory example, If you back up that directory on Monday using UltraDedup®, the first Chapter will be somewhere around five gigabytes (assuming that there is little redundancy in the Chapter). If 100 megabytes of data in that five-gigabyte directory changed between Monday and Tuesday and you back up the directory on Tuesday to an UltraDedup® archive, then the UltraDedup® archive will grow by about 110 megabytes. UltraDedup® will preserve the state of the first two Chapters perfectly.

A Chapter can contain millions of files and an UltraDedup® Archive can contain thousands of Chapters.

The Free Edition of UltraDedup® only allows for 3 Chapters and has other restrictions. Nonetheless, the Free Edition is still a very useful tool.