Compressed file formats all act as a carrying case for other files, and any file format can be compressed.  So once the file is uncompressed you will need other programs potentially to view the files.  To extract compressed files with Ultra File Opener, please do the following:

Right click on a compressed file (such as ZIP, RAR, 7Z, and Pages format and so on)
Move the mouse pointer over "Open with Ultra File Opener”
Select the “Extract” menu
Input or select a file location that you can easily find
Click OK

Then you can view the extracted files on the selected location.