There are so many of you have asked me how to use "Format Factory", today his spare time to sit and write images tutorials are okay:
Step 1: After installing Format Factory on the computer, open the utility
Step 2: On the interface of Format Factory, select Advanced mode -->Video Joiner

Step 3: Video Joiner dialogue opens, select output video format that you want. Click Add File or Add Folder to select videos needing to be joined.

After selecting videos needing to be joined --> click OK to return to the main interface.

Step 4: Click Start on the toolbar to start joining videos.

It is done, after joining videos successfully, you only need to access the directory containing the output videos and use built-in video players on the computer to watch these videos.
Good luck