For decades, programmers have hidden secret features and surprises inside the software they write. Such tidbits are known as Easter eggs, after the annual holiday hunt. (Note that undiscovered hard-boiled eggs may eventually create less pleasant surprises if left to mature in warm places.) As you're enjoying the Easter holiday, we've got a few links for Apple's Easter eggs.

For OS X Easter eggs, the Easter Egg Archive has a fairly comprehensive list that includes some classics; the BSOD Windows icon and the "here's to the crazy ones" copy on TextEdit's icon are particular favorites.

The classic Mac OS was populated with plenty of Easter eggs -- even inside the hardware itself -- but did you know that there was even an Easter egg in Inside Macintosh, the developer documentation for the Mac? has the story.

As OS X is built atop the BSD flavor of UNIX, it carried forward some truly ancient Easter eggs from the older operating system. The command-line calendar program's data files include some mythological/fictional anniversaries, including a disputed birthday list from Tolkien's The Lord of the Rings.

Apple's newest (and most portable) OS is no stranger to the Easter egg tradition, but the new hidden items have a speakable twist. Siri's subtle movie reviews and silly answers to simple questions have taken over for some of the spontaneous/secret items you might find on the Mac.

This article was originally published on Tuaw.
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