Combine multiple video and audio files into Single file

I recently observed some tricks to combine your video and audio files into a single file without using any additional softwares.These tricks are pretty simple to implement and work fine with many formats.
Trick 1:This one is based on something we do almost everyday,but may never have realized its full potential.

1.Download and install Winrar or Winzip(most of you would already have it !!!).
2.Suppose you have 3 videos in .mpg format that you want to combine.You have to add them into a zip or rar file.Note:An important thing to note here is that the files must be added without any compression.For eg. in Winrar,select and right click on the files you want to join,click on "Add to archive ",then in the compression method select "Store".
This way the files will not be compressed and the total file size will be the sum of individual components.
3.Now you will get the rar or zip file.Just rename the file as .mpg file(or .mp3 or whatever is the format of your individual files).You will get your combined video file!!!
Note:This works for many audio and video files and also with .flv files(the one you download from Youtube).Thus using this trick you can join multiple videos downloaded from YouTube.
Trick 2:This trick is also very simple to implement and works very fine with .mpg ,.flv and .mp3 files(May work with other formats,I have not tested all other formats)This does not work for avi files though.

1.Suppose you want to join 3 video(or audio) files into one.
2.Put all these files in a single folder.Create a blank text file in the same folder.
3.In the text file,type copy /b *.mpg FullMovie.mpg .For other formats replace .mpg with the appropriate extension.
4.Save the file with .bat extension(eg. convert.bat)
Note:if you dont know how to change the file extension read this.
5.Now double click on the convert.bat file.

A file named Fullmovie will be created which contain your combined video.You are done.Enjoy!!!