You may have used DOS's command line copy method but you might not have know that we can use Copy command to hide our files behind any picture or any other files. The following post will show you how to hide important files behind any picture or wallpaper.
We will need Win RAR installed for following trick.

Create a RAR of files which you have to hide. ex. "my-files.rar".

Take a picture/wallpaper you want your files to be hidden behind.
ex. "my-pic.jpeg" Move both files(myfiles.rar and wallpaper) in a temporary folder; say "d:\temp".

Open command prompt and make your prompt to path "d:\temp>".
Then type following command Carefully;

copy /b my-pic.jpeg + my-files.rar output.jpeg

and press enter.

This command will make output.jpeg by combining both my-pic.jpeg and my-files.rar files.

If you double click on output file it will open the picture associated with it, i.e my-pic.jpeg here, and if you want to open your rar files just open the output files with win-rar application.

Be Careful while typing cammand
 
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