Hide Files Inside of Image Files

1. Create a new folder on your HDD,
   Example: I create a folder in my D: drive and rename it as "Lesson". ( D:\Lesson )
* It better you follow my blue colored examples if you are a n00b.

2. Then drop the file(s) that you need to hide, into that folder. And also, place the image that you'll be using to hide the files in. In my case I have want to hide a text file ( Test.txt ) file inside a image file( Image.jpg ). So I put both files into D:\Lesson folder.

3. Now select the file(s) that you want to hide. Only select the files you want to hide, not the picture. (In my case I select only the Text.txt file.) Right-click on them; and choose the option to add them to a compressed RAR file. In order to accomplish this task, you will need to have either archiving or compression program such as WinRAR installed on your computer.

Name this RAR file whatever you want. I renamed it as “Secret.rar”.

4. Now click on Start, and then click on Run ( or press Windows Key + "r" ). It will open-up the run dialog box. In there type “CMD” without the quotes and press Enter.
It will pop-up the command prompt window.
Use "cd" command on command prompt to change the current working directory of the CMD in to your folder that contain the secret files. As my example I type cd D:\Lesson to get to the "Lesson" directory in D: drive.

5. If you successfully move to your folder on CMD, then type the following line:
"copy /b NameOfTheImage.JPG + NameOfZIPorRAR.rar NameOfNewSecretImage.jpg" ( without "s ) and press Enter.

In my example;

copy /b Image.JPG + Secret.rar SecretImage.jpg

If you success it will say "1file(s) copied.".

And that’s it! The image file will have been updated with the compressed archive inside! You can actually check the file size of the picture and see that it has increased by the same amount as the size of the archive. Now You can delete all other files except the SecretImage.jpg ( Newly build secret image. ).

You can access your hidden file(s) by simply change the extension to .RAR and open the file using WinRAR.
Then your hidden files show up and you can extract them out.
It may sound like a lot of work, but it's a pretty simple. That is all it takes to hide files inside JPG picture files! It’s a great way simply because not many people know it’s possible and no one even thinks about a picture as having to the ability to “hide” files. This is only a tiny trick. A kind of a foolproof method. But if you want to get really serious about encryption, you'll want to encrypt your data with TrueCrypt.

Good luck and keep exploring..!! ;)