Today feel like teaching you a bit of steganography - How to hide messages in images so you can send your message discretely and only certain people can retrieve it.
One tool to do steganography is JPHide and JPSeek that you can find in the internet. But you can only hide messages in jpeg file using this software.
First select the image that you want to use.
After the picture is selected, click hide to hide a message.
Then enter a password that will be used to open back the file later.
Then you need to select the file that you want to hide. As logic dictates, the file cannot be bigger than the picture..
After that don't forget to save or save as..
Then you can send the file over to your friend.
For the recipients, use the JPHS to open the file and then click seek, then enter the password, your friend MUST pass you the password earlier or you will not be able to retieve the message.
Then just save the files.
Enjoy..and FYI, the US suspect this is how terrorists pass messages among each other.
Of course there is a way to crack this technique, called steganalysis.