Steganography (, STEG-ə-NOG-rəfee) is the practice of concealing a file, message, image, or video within another file, message, image, or video. The word steganography combines the Greek words steganos (στεγανός), meaning "covered, concealed, or protected," and graphein (γράφειν) meaning "writing". The first recorded use of the term was in 1499 by Johannes Trithemius in his Steganographia, a treatise on cryptography and steganography, disguised as a book on magic. Generally, the hidden messages appear to be (or be part of) something else: images, articles, shopping lists, or some other cover text...

Shorthand is an abbreviated symbolic writing method that increases speed and brevity of writing as compared to longhand, a more common method of writing a language. The process of writing in shorthand is called stenography, from the Greek stenos (narrow) and graphein (to write). It has also been called brachygraphy, from Greek brachys (short) and tachygraphy, from Greek tachys (swift, speedy), depending on whether compression or speed of writing is the goal. Many forms of shorthand exist. A typical shorthand system provides symbols or abbreviations for words and common phrases, which can allow...