A virtual Easter egg is a hidden message or feature in an object such as a movie, book, CD, DVD, computer program, or video game. The term draws a parallel with the custom of the Easter egg hunt observed in many western nations. The earliest known reference to an Easter Egg as a hidden item in a medium appears to be from 1975's The Rocky Horror Picture Show, in which actual Easter eggs are visible in certain shots (under Frank N. Furter's throne, for example), from an Easter Egg hunt the crew had while filming.^[1] Atari's Adventure, released in 1979, contained what is thought to be the first video game Easter egg (the programmer, Warren Robinett's name).

In computer programming, the underlying motivation is often to put an individual, almost artistic touch on an intellectual product which is by its nature standardised and functional. It is analogous to signature motifs such as Diego Rivera including himself in his murals or Alfred Hitchcock's legendary cameos.

Computer-related Easter eggs

Software-based

Easter eggs are messages, graphics, sound effects, or an unusual change in program behavior that mainly occur in a software program in response to some undocumented set of commands, mouse clicks, keystrokes or other stimuli intended as a joke or to display program credits. They are often located in the "About" box of a software. An early use of the term Easter egg was to describe a message hidden in the object code of a program as a joke, intended to be found by persons disassembling or browsing the code.

Easter eggs found in some Unix operating systems caused them to respond to the command "make love" with "not war?" and "why" with "why not" (a reference to The Prisoner in Berkeley Unix 1977). The TOPS-10 operating system (for the DEC PDP-10 computer) had the "make love" hack before 1971; it included a short, thoughtful pause before the response. This same behavior occurred on the RSTS/E operating system where the command "make" was used to invoke the TECO editor, and TECO would also provide this response.

The largest Easter egg is purported to be in the Atari 400/800 version of , which contains an entire game that was more complex and challenging than the original Pitfall II. Many personal computers have much more elaborate eggs hidden in ROM, including lists of the developers' names, political exhortations, snatches of music, and (in one case) images of the entire development team. The 1997 version of Microsoft Excel contained a hidden flight simulator;^[2][3] the 1997 version of Word, a pinball game.^[4] The Palm operating system has elaborately hidden animations and other surprises. The Debian GNU/Linux package tool apt-get has an Easter egg involving an ASCII cow when variants on "apt-get moo" are typed into the shell. Another notable Easter egg is from The MathWorks' MATLAB: the why command provides succinct random answers to almost any question. % why % because the not very smart system engineer insisted on it

In Mac OS X operating systems, a recording of the Liberty Bell march, famous for being the opening theme of the British comedy sketch series Monty Python's Flying Circus can be found under /System/Library/Frameworks/Python.framework/Versions/2.3/lib/python2.3/test/. In Mac OS X version 10.4, the recording (audiotest.au) plays "Nobody expects the Spanish Inquisition!"

Another Easter Egg is found on all Microsoft Windows Operating Systems prior to XP. In the 3D Text screen saver, entering the text "volcano" will display the names of all the known volcanoes that exist in the world. Microsoft removed this Easter Egg in XP but added others. One in XP is to simultaneously hold the Alt, shift and the number 2 keys in the Solitaire game to produce a forced win.^[5]

Non-software

While computer-related Easter eggs are often found in software, occasionally they exist in hardware or firmware of certain devices. On some PCs, the BIOS ROM contains Easter eggs. Notable examples include several early Apple Macintosh models which had pictures of the development team in the ROM (accessible by pressing the programmer's switch and jumping to a specific memory address, or other equally obscure means), and some errant 1993 AMI BIOS that on 13 November proceeded to play "Happy Birthday" via the PC speaker over and over again instead of booting. Similarly, the Radio Shack Color Computer 3's ROM contained code which would display the likenesses of three Microware developers on a <ctrl><alt><reset> keypress sequence - a hard reset which would discard any information currently in the dynamic memory.^[6]

Perhaps the most famous example of a hardware Easter egg is in the HP ScanJet 5P, where the device will play the Ode to Joy or Für Elise by varying the stepper motor speed if users power the device up with the scan button depressed [1]. Another Easter egg is found in the Kurzweil K2x musical keyboard series (K2500, K2600 and others): if users type "Pong" while in search mode they can play the game Pong. The EEPROM of Nagra smart cards for the Dish Network satellite television system contain the phrase "NipPEr Is a buTt liCkeR". Nipper was a hacker who broke old security routines on the cards, and this text is included as a fallback to old security routines, where the phrase was hashed against an input text to verify the card. Several Oscilloscopes have been known to contain Easter eggs. One example includes the HP 54622D known to play Asteroids.

Chip and PCB-based Easter eggs

Main article: Chip art

Many integrated circuit (chip) designers have included hidden artwork, including assorted images, phrases, developer initials, logos, and so on. This artwork, like the rest of the chip, is reproduced in each copy by lithography and etching. These are visible only when the chip package is opened and examined under magnification, so they are, in a sense, more of an "inside joke" than most of the Easter eggs included in software.

Originally, the Easter eggs served a useful purpose as well. Not unlike cartographers who may insert trap streets or nonexistent landscape features as a copyright infringement detection aid, IC designers may also build non-functional circuits on their chips to help them catch infringers. Easter eggs, however benign, if directly copied by the defendant, could be used in mask work infringement litigation. Changes to the copyright laws (in the USA, the Semiconductor Chip Protection Act of 1984, and similar laws in other countries) now grant automatic exclusive rights to mask works, and the Easter egg no longer serves any practical use.

Western Digital's MyBook Pro has several words on the metal band that wraps around 3 sides in Morse Code. The code reads: PERSONALRELIABLEINNOVATIVESIMPLE INNOVATIVEPERSONALDESIGNRELIABLE INNOVATIVEDESIGNPERSONALDESIGN SIMPLEINNOVATIVE

The Commodore Amiga models 500, 600 and 1200 each featured Easter eggs, in the form of titles of songs by The B-52's etched on the motherboards. The 500 says "Rock Lobster", the 600 says "June Bug", and the 1200 says "Channel Z". The Amiga OS software includes a variety of hidden messages as well.^[7]

Several models of S3 Trio 64v+ graphics cards have the Beatles lyrics printed faintly along the edge of the card.

Easter Eggs in Movies and DVDs

Easter Eggs in theatrical movies are often found at the end of the credits, when most of the audience has probably left. Pirates of the Caribbean did this in all three movies. Ferris Bueller's Day Off, Look Who's Talking Too, See No Evil, and Thirteen Ghosts also did this.

The Easter Egg has also found new life in DVD. In some cases, an extra click to the right or left, or going up in the menu instead of going down to select a choice will bring up a hidden feature, including concept art, humorous outtakes, or deleted scenes.

Security concerns

Because of the increase in malware, many companies and government offices forbid the use of software containing Easter eggs for security reasons. With the rise of cybercrime and the prevalence of the Easter egg's "cousin", the logic bomb, there is now concern that if the programmer could slip in undocumented code, then the software cannot be trusted. This is of particular concern in offices where personal or confidential information is stored, making it sensitive to theft and ransom. For this reason, many developers have stopped the practice of adding Easter eggs to their software. Microsoft, who has in the past created some of the largest and most elaborate Easter eggs such as the ones in Microsoft Office, no longer allows Easter eggs in their software as part of their Trustworthy Computing initiative.^[8]

See also

• Hidden track
• Undocumented feature
• Easter eggs in Microsoft products

Notes

External links

• Easter eggs and the Trusted Computing Base – Network World article outlining the concern over Easter eggs
• Chip Fun: Microchip-based Easter eggs – From the National Museum of American History; photos by Integrated Circuit Engineering Corp.
• Digital Press' classic video games Easter egg compendium
• Lee's PeeknPoke Issue 5 – PDF retro game magazine with Atari 2600 hidden Easter egg feature
• Software Tips and Tricks – Details on Easter eggs found in operating systems and applications.
• Egg Heaven – Gives details on virtual Easter eggs in software, games and other popular media products.
• DVD Easter Eggs – Lists many Easter eggs in DVDs
• The Easter Egg Archive – large archive of all kinds of Easter eggs.
• Easter egg: Information from Answers.com – Includes history of Easter eggs.