You can easily hide a file in inside the image this method called as steganograph.
It's a technique using which we can exchange data across the world over internet
without using any encryption or decryption method.
Step 1:
Create new folder in your system and move the file and image to same folder
Step 2:
Make rar or zip for which file you want to hide
Step 3:
Open the comman prombt
Step 4:
Go to the folder location
eg: d:\sample folder\>
Step 5:
enter the following command
copy /b sample.jpg+sample.rar sample1.jpg
Step 6:
Now finished the process and check the image size of sample1.jpg
(if you have any clarification and details pls comment)












