Why Software Developers Hide Easter Eggs in Code

Thousands of articles have been written and thousands of videos made about Easter eggs in games. But for some reason, humanity persistently ignores Easter eggs in other types of software. Yet they are just as old as software itself. These are undocumented features or messages that developers hide in code or hardware. You can find them literally everywhere: from prehistoric operating systems to modern browsers.

AI won't do this. It's documented that one of the very first Easter eggs at Atari was created to immortalize a developer's name in the code.

What Makes an Easter Egg

In software, an Easter egg is a small hidden part of a program. To qualify as an Easter egg, a feature must meet three criteria:

• It must be entertaining and harmless
• It must be undocumented, unexpected, but reproducible
• It must have personal meaning to the programmer

The Rust programming language systematically included a Lovecraft quote invoking Cthulhu in its core library until January 2015.

The First Easter Eggs

The first hidden messages appeared in mainframes in the late 1960s. In 1979, the game Adventure for the Atari 2600 became a turning point.

Atari's management did not allow developers' names to appear in games — they feared competition and salary demands. Warren Robinett, the creator of Adventure, programmed a secret room containing the phrase: "Created by Warren Robinett."

After hundreds of thousands of cartridges had been distributed, a 15-year-old teenager from Salt Lake City discovered the Easter egg and wrote a letter to Atari. The director of software development, Steve Wright, called it an "Easter egg" and decided to make it company policy to include hidden features in future games.

In Fairchild Channel F games (1976) — Video Whiz Ball and Alien Invasion — certain key combinations revealed the programmers' names.

Microsoft's Easter Eggs

In Windows 1, the list of developer names remained hidden for 37 years and was discovered only in 2022.

In MS-DOS (up to version 6.2), pressing F1 in the About tab displayed: "No Help Available (so leave me alone)."

Excel versions 5.0 through 9.0 contained mini-games. The first was The Hall of Tortured Souls, described as a "Doom-style mini-game."

Office 97 had games in all its components:

• Excel: a hidden flight simulator
• Access: a Magic 8-Ball simulation
• Word: a pinball game

The 3D Text screensaver in Windows (up through XP) would display the names of all US volcanoes when you typed "volcano."

Microsoft officially stopped adding Easter eggs in 2002 as part of the Trustworthy Computing Initiative. Later, Easter eggs returned: Asteroids in Office 2004 for Mac, and a silhouette of Bill Gates in Outlook 2010.

In Windows XP: if you typed "bush hid the facts" in Notepad and saved it, when you reopened the file the text was replaced with a string of null characters.

Google's Easter Eggs

Google actively adds Easter eggs to its products. Google Search contains numerous hidden features:

• Searching "anagram" — rearranges the search results
• "do a barrel roll" — rotates the entire page
• "askew" — tilts the page to the right
• "Bletchley Park" — a nod to the WWII codebreaking headquarters

Google Maps and Google Earth are full of references: a flight simulator (Tools → Flight Simulator, Ctrl+Alt+A), and the moon once turned into cheese when you zoomed in all the way.

Removed Google Maps jokes included: a route from New York to London suggesting you swim across the Atlantic; Tokyo to Los Angeles — by kayak; Snowdon to Brecon Beacons — by dragon.

The site elgoog.im preserves interactive Google Easter eggs. The Thanos egg (April 2019) let you see the snap effect — half the search results would dissolve. Enhanced versions of the Dinosaur game, Snake, and Pac-Man are also available.

Google has kept some useful Easter eggs: "flip a coin" and "roll a die" still work.

Legendary Easter Eggs

The Most Hidden: Donkey Kong (Atari version) contains the initials of Landon M. Dyer, which appear after Mario dies. The programmer himself revealed the secret after many years.

The Most Complex: Trials Evolution (2012) contains a multi-layered puzzle:

• Encrypted messages on wooden planks visible during gameplay
• Graphical analysis reveals Morse code
• Directions to a website with another puzzle
• Coordinates of four locations: Bath, Helsinki, San Francisco, Sydney
• Sealed chests with keys at those locations
• The next stage — the first Saturday of August 2113 (August 5th)
• A mysterious chest buried under the Eiffel Tower in Paris
• A man with an umbrella will bring a briefcase in the year 2113

The Most Popular: The Konami Code — the sequence "↑↑↓↓←→←→BA." First used in Gradius, it became famous in Contra (30 lives instead of 3). It has been programmed into more than a hundred games.

The Konami Code has been referenced by Google, Digg, ESPN (2009 — an explosion of unicorns and hearts), BuzzFeed, Google Stadia, and Contra: Rogue Corps. There's even an episode about it in the animated series The Amazing World of Gumball.

The Most Unexpected: μTorrent contained Tetris. The command "T" in the About menu launched a classic Tetris game.

The Creepiest: Oculus VR (2019) — controllers contained the messages "Big Brother is watching you" and "The Masons were here." These were intended only for prototypes but accidentally made it into consumer devices.

The Most Expensive: Bitcoin — Satoshi Nakamoto's first block contains an encoded message. Decoded, it reads: "The Times 03/Jan/2009 Chancellor on brink of second bailout for banks." It was likely a statement about the global financial crisis.

Conclusion

Easter eggs have existed since the dawn of programming. The Easter Egg Archive website contained 13,998 entries in 2011 (adding 18 every two weeks). Now it has 14,450, with the last addition in August 2015.

Steve Wozniak and Steve Jobs considered Easter eggs a sign of attention to detail and humanity. They distinguish humans from robots through emotion. Discovering an Easter egg evokes surprise, delight, laughter, and a connection with the developer.

Programmers will continue adding personality to code despite security requirements. The need for self-expression guarantees that Easter eggs will endure.