Uni-Tree is a kind of software for file categorizing and query with the use of set calculation among file-sets. It  built  based on a new kind of directory theory called "dynamic-set-directory" or "hyper-tree-directory", which  have great advantage over traditional directory tree. There is no fixed path in it, you can get files in deferent "path"  you fill convenient.

The  function mainly consists of two procedures. Firstly, classify various files to different file-sets. Secondly, search the needed ones by means of set calculation (mostly intersection operation).

Compared with traditional directory tree, Uni-Tree has the following extraordinary advantages:

1.Meeting users` different searching needs by using dynamic combinations:

In the traditional system, the path of query is static. For example, if a user has set up a file for storing American science fiction film, the only way to find the file is to follow the path "American/ science fiction /films". That is to say, they need to query  "America" ,then "science fiction", and finally  "Films". But only for American films or science fiction films, it will be time-consuming.

 On the contrary, no fixed path exists in Uni-Tree. It enables users to gain every needed files by dynamic combinations formed by set calculation forming. So if users want American action films, users only need to perform intersection among  "America", "science fiction" and  "Films". And for finding American films ，another intersection between  "American" and "Films" will satisfy you.

2.Solving the conflict that a file only can be classified to one folder:

  In traditional system, a file is only can be placed in one folder. However, users would feel inconvenient when they want to store a file into several folders at one time. For instance, it is quite easy for users to categorize an mp3 file to the corresponding folder by the singer`s name; but if this song is performed by several singers, it can`t work. On the contrary, Uni-Tree can solve this problem since it has the function of storing one file in several file sets at the same time.

3.Being convenient for users to get files by variational paths:

   Uni-Tree has an inquiry guiding system, with which users are able to query files from wilder range to narrow one until they find the file. Besides, the results are displayed in groups, which is easier for users to browse. For example, if users want to find all American action films, they can follow such steps. Firstly, find all the film files. Then, with the direction of this inquiry guiding system, exert the intersection operation between the results you`ve got and ?American?, and finally with ?action?. If you want the results to be showed in group by theme, that is in the name of films, another intersection operation between the results and ?Topic? will meet your demand.