Easy linux cli steganography no additional packages needed, but you can use them for more options for hiding/encrypting (thanks @kravietz for this discovery). Steganography is term for hiding one file into another.

1. Zip any file and have one simple.jpeg image
2. In your cli type: cat simple.jpeg file.zip > hidden.jpeg

hidden.jpeg is same image but different in size, summing up to file.zip+simple.jpeg