Steganography software is the digital equivalent of invisible ink. It lets you embed data inside other files. Secret data, of course. So why use steganography – why not just ZIP your files with password protection? Well, when you have a password – protected file of any sort, there’s something to be explained if and when someone (like your mom or boss!) notices it. Besides, passwords aren’t completely safe.
With steganography, no-one will even know there’s something hidden! Using the technique, you hide your file inside another, known as the carrier file. Hide In Picture is once such tool: you can embed files into GIF and BMP images. You retrieve your data from the carrier file just by clicking Extract in the program. You can also password-protect the carrier file if you’re so paranoid you think only you’ll survive, and then embed that into another file.Download it from http://source-forge.net/projects/hide-in-picture.
A similar program is wbStego4open. This open-source, cross-platform tool allows you to embed data in BMP, text, HTML, and PDF files! Get this one from http://wbstego.wbailer.com. There are stego programs that allow you to embed data in zipped archives too. wbStego4open has two modes — Wizard and Flowchart. The latter allows users we call “advanced” to embed / extract data, password-protect files, and compress the carrier file, all in one window.
Steganography opens up a cool one top-corporate-boss-to-another way of exchanging secret messages via e-mail. The sender and receiver need to have the same software installed, of course.