[How] combine several parts of a file

When you have a lot of separate file parts, how you gonna combine all these file parts into one? 
Let's check out of this snapshot.

Why to create a new folder for those file parts?
Answer: To make clear view for ourselves, and won't mess up the whole progress.

The steps to combine all the file parts are very easy,
We only need to use "copy /b" command to combine all the file as the snapshot shown.

No matter what time of file extension, even movie, music files, you able to use this command to combine all your file parts rather then use other softwares.