What Is an Easter Egg? The History of Hidden Surprises in Software and Games

An easter egg is a hidden message, joke, image, or feature tucked inside software, a video game, a movie, or a website by its creators. It is not a bug. It is not a feature in the marketing brochure. It is a secret that rewards anyone curious enough, patient enough, or weird enough to find it. The first software easter egg landed in 1979, inside an Atari game, and the idea has been quietly mutating across every screen you own ever since. This is the story of how a small act of programmer rebellion turned into a permanent layer of internet culture.

Easter eggs sit in a strange spot. They are official, in the sense that the people who built the thing put them there on purpose. They are also unofficial, in the sense that nobody is told about them. You stumble into them. You hear about them on a forum. The hunt is half the point.

Table of Contents

• What Is an Easter Egg? A Working Definition
• The First Software Easter Egg: Atari, 1979
• Why Easter Eggs Exist (and Why Companies Eventually Tolerated Them)
• Types of Easter Eggs You Will Actually Encounter
• Famous Easter Eggs That Shaped the Format
• Easter Eggs vs Cheat Codes vs Glitches
• Easter Eggs in 2026: Where They Live Now
• How to Find Easter Eggs Without Reading Spoilers
• Frequently Asked Questions

What Is an Easter Egg? A Working Definition

The term easter egg is borrowed from the old tradition of hiding decorated eggs around the house at Easter and letting kids hunt them down. The metaphor is exact. Something is hidden on purpose. Someone is meant to find it. The reward is the finding itself, not the egg.

In software, an easter egg has to clear a few bars to count. It has to be intentional, not a side effect of a bug. It has to be hidden, not promoted in the docs. It has to be findable, even if the steps are absurd. And it has to be decorative. A hidden tool that does real work is an undocumented feature. An easter egg is a joke, a tribute, a signature, or a wink.

The format is flexible. It can be a hidden room in a game, a secret credits screen, a funny response to a typo in a search engine, a Konami Code sequence on a corporate website, a frame of animation that lasts a tenth of a second. The unifying thread is that the creator is talking directly to whoever bothers to look closely. It is the same culture of inside jokes that gave us things like copypasta and other internet folklore, just smuggled into the code instead of the comment section.

The First Software Easter Egg: Atari, 1979

The first widely recognised software easter egg lives inside Adventure, an Atari 2600 game from 1979. The programmer, Warren Robinett, was annoyed. Atari refused to put developer names on game boxes, partly to stop rivals from poaching talent. Robinett had built most of Adventure alone. He wanted credit. He took it.

He created a hidden room. To reach it, a player had to find a single grey pixel called the Grey Dot, carry it through a wall, and enter a chamber that displayed “Created by Warren Robinett” in flashing colours. He told nobody at Atari. He shipped the cartridge. He left the company. Months later, a teenager in Salt Lake City found the room and wrote in. Atari panicked, considered patching it out, then realised players loved it, and leaned in. The internal memo reportedly called these secret features “easter eggs.”

The phrase stuck. It became the Atari term, then the industry term, then a word everyone uses. Robinett did not know he had invented a genre.

Why Easter Eggs Exist (and Why Companies Eventually Tolerated Them)

Easter eggs exist because software is made by people, and people get bored, get cheeky, and want to be remembered. For most of the 1980s and 1990s, programmers slipped hidden credits, photos of themselves, and entire mini-games into commercial software without telling marketing. Microsoft Excel 97 contained a hidden flight simulator. Word 97 had a hidden pinball game. Photoshop hid the face of a small dog called Merlin in its splash screen for years. Quark, Adobe, Lotus, and Apple were all doing it.

The Sarbanes-Oxley moment

The party did not last. After the Sarbanes-Oxley Act in 2002, large American software companies started auditing every line of shipped code. Hidden, unaudited features in financial-grade software were a compliance nightmare. Microsoft officially banned easter eggs in its enterprise products under the Trustworthy Computing initiative. Other vendors followed. For a stretch in the mid-2000s, easter eggs in serious office software went almost extinct.

The web brought them back

Then the web arrived in force, and easter eggs came roaring back in a new shape. Google search results, browser developer consoles, streaming services, indie games, and millions of small websites suddenly had room to hide jokes. Web code was cheaper to ship and easier to patch. Marketing teams figured out that a viral hidden feature was free advertising. The easter egg stopped being a programmer rebellion and started being a brand strategy. The spirit shifted, but the format survived.

Types of Easter Eggs You Will Actually Encounter

Easter eggs come in clusters. After forty years, the form has settled into a handful of recognisable shapes.

• Hidden credits. The original kind. A secret screen, often triggered by a key combination, that names everyone who worked on the project.
• Mini-games. A whole game tucked inside something that is not a game. The Chrome dinosaur that runs when you have no internet is the most-played mini-game on Earth.
• Pop culture references. Lines from films, music, comics, or older games quoted in dialogue or environment art. Sometimes subtle, sometimes an entire room shaped like the bridge of the Enterprise.
• Search engine jokes. Google’s “do a barrel roll” rotating the page, “askew” tilting it, “Atari Breakout” turning image search into a game. Advertising and easter egg in the same gesture.
• Movie post-credits scenes. The film world version of the same instinct. A scene that runs after the credits as a reward for the people who waited.
• URL and console eggs. Hidden pages on a corporate site, jokes in the browser developer console. Reddit, GitHub, Stripe, and Cloudflare all hide things here.
• Hardware eggs. Engravings inside laptop cases, hidden text on printed circuit boards. The original Macintosh team had their signatures cast into the inside of the plastic case.

Famous Easter Eggs That Shaped the Format

A few easter eggs went so deep into culture that they became reference points on their own. They are worth knowing because most modern easter eggs are quoting them in some way.

• Warren Robinett’s hidden room, Atari Adventure, 1979. The genesis.
• The Konami Code, 1986. Up, up, down, down, left, right, left, right, B, A. Originally a debug shortcut in Konami’s Gradius, it spread to dozens of Konami titles and thousands of websites. We told the full Konami Code story here.
• Excel 97 flight simulator. Type a specific cell reference, hold the right keys, and Excel turned into a low-fi 3D flight engine over an alien terrain with the dev team’s names written into the ground. A spreadsheet was secretly a flight game.
• Half-Life developer commentary nodes. Valve hid full audio commentary tracks inside the game world, anchored to physical objects you walked past.
• Google “the answer to life, the universe and everything”. Type the phrase into Google and the calculator returns 42. A nod to Douglas Adams, live for two decades.
• The Wilhelm Scream. Not strictly software, but the same instinct. A stock audio scream slipped into hundreds of films since 1951 as a private inside joke. Once you know it, you cannot unhear it.
• Tesla cars’ rainbow road. Holding the autopilot lever turned a stretch of the dashboard map into a Mario Kart style rainbow road. Pure decoration, pure easter egg.

Easter Eggs vs Cheat Codes vs Glitches

People mix these three up constantly, and it is worth keeping them separate, because they have different origins and different rules.

• Easter eggs are intentional, hidden, and decorative. The goal is delight, not power.
• Cheat codes are intentional, hidden, and functional. They change the rules of play, usually for the player’s benefit, like infinite ammo or skipping levels. The Konami Code started life as a cheat code before it crossed into easter-egg territory through repeated cultural use.
• Glitches are unintentional. They are bugs the developer did not plan, did not test for, and often does not know about until players post videos. Speedrunners live on glitches. Glitches sometimes get adopted as features and reclassified as easter eggs in later releases, but they did not start that way.

The honest way to tell them apart is to ask one question: was a human supposed to find this? An easter egg, yes. A cheat code, yes. A glitch, no.

Some genres play with this distinction. The whole Metroidvania genre rewards the player for noticing things the game never tells them about, which is one step from an easter egg promoted to first-class mechanic.

Easter Eggs in 2026: Where They Live Now

The format is alive and has migrated to every screen with code behind it. Modern easter eggs live in places the 1979 Atari team could not have predicted.

• Streaming platforms. Netflix, Disney+, and Prime Video hide secret category codes you can append to a URL to unlock unlisted genres. The same engineering layer that makes video streaming work at scale is where those hidden URL hooks live.
• AI assistants. Ask Siri, Alexa, or Google Assistant absurd questions and the engineers have written response after response. “What is the airspeed velocity of an unladen swallow?” gets a Monty Python answer on every major assistant.
• Browser developer consoles. Open the console on Reddit, GitHub, or Cloudflare and the company has put ASCII art, hiring messages, or jokes there. It is aimed only at the small percentage of users who press F12. The console also exposes the plumbing behind sites, including the DNS resolution chain that routes every easter-egg request you fire off.
• Video games, still. Indie games in 2026 ship with denser easter-egg layers than ever. Tunic, Animal Well, and Outer Wilds turned the easter egg into a structural design philosophy. The hunt is the game. See our best indie games of all time roundup for more.
• Films and shows. The Marvel and Star Wars expanded universes treat easter eggs as a fan-service economy, with single-frame references designed to be paused and dissected on social media within hours of release.
• Hardware. Apple still hides messages inside chip silicon. PCB designers slip cat doodles, song lyrics, or thank-you notes into the silkscreen layer of circuit boards.

For a developer or designer in 2026, hiding a small joke in your work is one of the few gestures that still feels personal in an industry that has industrialised almost everything else. That is probably why the format refuses to die.

How to Find Easter Eggs Without Reading Spoilers

Finding easter eggs yourself is more satisfying than reading a list someone else made. A few habits help.

Poke at the edges

Most easter eggs sit at the boundary of a system. Try the about menu, the settings page nobody opens, long-pressing icons, double-clicking logos, holding shift while clicking the version number. The Mac OS About box used to reveal the development team if you held option. That pattern repeats everywhere.

Type the obvious nonsense

In search engines, type the joke you would write if you were a bored engineer. “Do a barrel roll.” “Zerg rush.” “Recursion.” Google has been hiding things behind queries like these since 2009.

Open the developer console

Right-click, inspect element, console tab. On many large sites the engineering team has left a message there. It is not invasive. It is a hello.

Watch the credits

Stay through the end credits of films and games. Some of the best easter eggs are placed exactly where almost nobody looks, because the people who do are exactly the audience the creator wanted to reach.

Frequently Asked Questions

Where does the term easter egg come from?

The term is borrowed from the religious and folk tradition of hiding decorated eggs around the house for children to hunt at Easter. The software meaning was popularised at Atari in 1980 after players discovered Warren Robinett’s hidden room in the game Adventure, and Atari executives needed a friendly word to describe the practice.

Are easter eggs legal? Can a company put one in any software?

Easter eggs are legal in most consumer software, but in regulated industries they have largely been stamped out. After the Sarbanes-Oxley Act in 2002 and similar audit-driven rules, financial, medical, and government software is expected to ship without any unaudited hidden code. That is why you will find easter eggs in browsers, games, and consumer apps, but almost never in your bank’s mobile app.

What is the difference between an easter egg and an undocumented feature?

An undocumented feature does real, useful work that just was not written into the manual, often because the product team ran out of time. An easter egg is decorative or playful and serves no operational purpose. The functional test is whether the hidden thing helps you finish a task. If yes, undocumented feature. If it makes you laugh, easter egg.

What was the first easter egg ever?

The first widely recognised software easter egg is Warren Robinett’s hidden credits room in the 1979 Atari 2600 game Adventure. There are earlier hidden messages in mainframe code from the 1960s and 1970s that some historians count as proto easter eggs, but Robinett’s is the first one that became famous, was deliberately designed to be found by players, and gave the practice its name.

Do easter eggs still get added to modern software?

Yes, and arguably more than ever, just in different places. They have migrated from desktop applications into web pages, browser consoles, AI assistants, streaming services, and indie games. Some studios, like the teams behind Tunic and Animal Well, have built entire game design philosophies around the easter-egg-as-structure idea. The format is not shrinking, it is moving.

Conclusion

Easter eggs are the human fingerprint on a medium that pretends to be machine-made. They started as a programmer signing his game in protest, and they survived because every generation of builders feels the same itch to leave a small, weird gift for whoever is paying attention. The invitation is the same everywhere. Look closer. Someone hid something here for you. The cat approves of any tradition that rewards curiosity.

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