11 Weird Windows Bugs and Easter Eggs You Have to See
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Microsoft started eliminating Easter Eggs when it launched its Trustworthy Computing Initiative in 2002. But you can still find a number of hidden features and weird bugs in Windows that are almost as good as real Easter Eggs.

And while most Windows errors tend to be a pain, some are actually quite entertaining. Care to discover them with us?

Windows 7 to Windows 10 Easter Eggs

Unless mentioned otherwise, the following Easter Eggs will work in all current versions of Windows.

1. God Mode

This hidden Windows feature was first introduced with Vista and remains one of the more useful ones. God Mode How to Enable God Mode in Windows 7, 8.1, and 10 How to Enable God Mode in Windows 7, 8.1, and 10 Windows has a hidden shortcut to view all system settings at once. Here's how to easily get to God Mode. Read More , also known as Windows Master Control Panel, unlocks an unexpected overview of all Control Panel options in one single folder. If you still use the Control Panel on a regular basis, you will love this trick!

To enable God Mode, create a new folder and use the following string of characters as its name.

GodMode.{ED7BA470-8E54-465E-825C-99712043E01C}

Et voilà, your master control panel is ready to use.

Note: You can replace the term “GodMode” with a term of your preference.

2. Star Wars CMD Code

Star Wars CMD

The Star Wars CMD code is one of the coolest command prompt Easter Eggs. And it works on all operating systems that support Telnet and have a terminal or command line, including Windows 10. Before you can use the command, however, you have to enable Telnet.

In Windows 10, press Windows + Q, type telnet, and select Turn Windows features on or off from the results. Scroll down until you see the Telnet Client entry, check the box, and click OK. Wait for Windows to complete the requested changes, then click Close.

How to Enable Telnet Client in Windows

Now it’s time to have some fun with Telnet! Press Windows + R to launch the Run menu, type cmd, and hit Enter to open the command prompt. Now run the following command:

telnet towel.blinkenlights.nl

Time to lean back and watch Star Wars in ASCII characters.

3. Slide to Shut Down

Microsoft hid an EXE file called SlideToShutDown SlideToShutdown: The Best Hidden Feature of Windows 10? SlideToShutdown: The Best Hidden Feature of Windows 10? Windows 10 is full of hidden tricks, and some of them are really cool -- like the little-known SlideToShutDown command! Read More in the C:\Windows\System32 folder. This alternative way to shut down Windows How to Shut Down Windows 10: 7 Tips and Tricks How to Shut Down Windows 10: 7 Tips and Tricks You can customize almost every Windows feature. We'll show you seven ways to improve the shutdown process. Soon you'll terminate Windows like a geek. Read More was first introduced with Windows Phone and then made it over to Windows 8. It’s great to turn off tablets, but also lets you shut down Windows on your desktop.

When you’re in tablet mode, try pressing the power button for 3-5 seconds and SlideToShutDown will self-launch. If you’re using Windows on a desktop, create a shortcut to launch this shutdown option.

4. Phone Dialer

Windows Phone Dialer

Ever since Windows 95, Windows contains a dialer app that will let you place a call through your computer’s phone port (if available). The only way to launch this utility is through calling the executable directly. Press Windows key + R, enter dialer.exe, and click OK.

5. Windows Calculator Rounding

Windows Calculator Rounding Error

To kick this one off, let’s do some basic maths together. First, try to answer the two questions below, then highlight the lines to see the answers.

  1. What is the square root of four? It’s two, isn’t it?
  2. And what do you get if you subtract two from two? Zero, right?

Now let’s do the above calculation using the Windows calculator 9 Neglected Windows Calculator Features to Save Your Day (and Money) 9 Neglected Windows Calculator Features to Save Your Day (and Money) The classic Windows Calculator contains many overlooked features. We bring them to light and show you how you can use this app to do math faster, process unusual calculations, and save money. Read More . Type in 4, take the square root and from the result subtract 2. What result does the Windows Calculator give you? See why they don’t want you to use calculators at school?

This bug has been around since the birth of Windows. The programmatic calculation method limits the precision of advanced calculations to 32 digits. This means that a complex calculation, like taking the square root, works with approximate numbers. For example, the calculator stores the square root of two as 1.99999… (with 32 instances of the number 9). This arbitrary-precision arithmetic (that’s its actual name!) can lead to tiny errors like the one we demonstrated above.

6. The Number of the Beast

Windows Port 666 Doom

Doom 95 was the first Windows version of the game Doom. The game used port 666, in reference to The Number of the Beast. And port 666 remains reserved for doom until this day.

To see for yourself, head to C:\Windows\System32\drivers\etc and open the file called services in Notepad.

7. Exit Explorer

The Windows 10 Taskbar context menu 3 Advanced Tips & Tricks For Using Windows Explorer 3 Advanced Tips & Tricks For Using Windows Explorer Windows Explorer is the default Windows file manager. Last week I introduced you to 3 easy ways to improve Windows 7 Explorer by tweaking features and using it to its full potential. In this article,... Read More contains a hidden option called Exit Explorer.

Hold Ctrl + Shift while right-clicking an empty space on the Taskbar. (If you’re running Windows 7 or lower, try right-clicking the Start Menu while pressing Ctrl + Shift.) In Windows 10, you should now see Exit Explorer as the very last item in the Taskbar context menu. This option lets you terminate the Windows File Explorer without having to go through the Task Manager.

8. Naming and Renaming Folders

Windows Naming Renaming Folders

Try to create a folder named CON and you will see the following thing happening:

The same thing happens when you try any of the following names:

PRN, AUX, LPT# (with # being a number), COM#, NUL, and CLOCK$

All of the above names are reserved for device names, meaning you cannot use them as file or folder names, regardless of the file extension. This is a relict from DOS, which has made its way through all versions of Windows, including Windows 7.

9. Microsoft Word Easter Egg

Microsoft Word Rand

This isn’t a bug, but a nicely hidden feature. Open Microsoft Word and type the following: = rand(5,10)

Microsoft Word should create 5 paragraphs of text with (in theory) 10 lines (in my example, it’s one line short). It’s nothing more than a dummy or placeholder. And depending on the numbers you pick, you can make it appear in many more paragraphs and copies. Try =rand(1,1) to show only one single placeholder sentence. The trick is also known as = rand(200,99).

The text will vary, depending on your version of Office and your primary system language. In Microsoft Word 97 through 2003 with English as the primary language, you’ll see the iconic sentence “The quick brown fox jumps over the lazy dog,” which contains all letters of the alphabet. Since Office 2007, the default text has been taken from a Word tutorial and also changed from Word 2013 to Word 2016. To bring back the iconic sentence in Word 2007, 2010, and 2013, type =rand.old() and press Enter.

If you’d rather use the standard Lorem ipsum dolor sit amet placeholder text What Is Lorem Ipsum & Where Did It Come From? [In Case You Were Wondering] What Is Lorem Ipsum & Where Did It Come From? [In Case You Were Wondering] Read More , type =lorem(X) to get X paragraphs of this filler text.

Note: The Replace text as you type feature (File > Options > Proofing > AutoCorrect Options > AutoCorrect tab ) must be turned on for this feature to work.

Windows XP Easter Eggs

Microsoft has fixed a few of the weird bugs we’ve covered in the past. Here are two that didn’t survive in subsequent Windows versions.

10. Bush Hid the Facts

Bush Hid the Facts

This Windows Notepad bug doesn’t work in Windows Vista or Windows 7, but if you’re still running Windows XP, give it a try.

Launch Notepad and type the following sentence: Bush hid the facts

Now save the file as anything you like, close it and open it again. What do you see?

If you did this in Windows XP, you’d see some weird Unicode characters or Chinese characters like in the screenshot above.

The explanation for this bug lies in the Windows function “IsTextUnicode”. The sequence of one four-letter, two three-letter, and finally one five letter word creates a so-called mojibake; Windows thinks it’s dealing with Chinese Unicode and when you save the document encodes it as such. When you re-open the document, it then displays Chinese characters, rather than the sentence you had entered.

11. Windows Solitaire Bug

Here is another bug that appears to be fixed in Windows 7. Please try it if you have Windows XP.

Open Solitaire and click the following key combination: Alt + Shift + 2

What happens is that the game ends right there and you see the cards falling to the front as they do when a game is completed successfully.

Happy Easter Egg Hunting in Windows

If you enjoyed reproducing these bugs, you might also enjoy our articles on the strangest Windows 10 apps For Real? The Strangest Apps on the Windows Store For Real? The Strangest Apps on the Windows Store The Windows Store is full of amazing tools, some spam, and a number of really strange apps. We highlight the most entertaining apps and amusing games we could find. Read More , resolved Windows mysteries 7 Windows Mysteries You Never Understood Resolved 7 Windows Mysteries You Never Understood Resolved Ever wonder what happens when you delete a file or what accounts run before you log in? We reveal the secrets behind these and other Windows mysteries. Read More , fun things Cortana will say Cortana Talks Back: Laugh, Cry & Love With Windows Phone's Digital Assistant Cortana Talks Back: Laugh, Cry & Love With Windows Phone's Digital Assistant Bored with no one to talk to? Why not strike up a conversation with your Windows Phone? These cues will make Cortana talk. Read More , and ridiculous Windows errors The 12 Most Ridiculous Windows Errors of All Time The 12 Most Ridiculous Windows Errors of All Time You probably see plenty of boring Windows error messages every day. Come enjoy some ridiculous ones, just for laughs. Read More .

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  1. Nick
    February 3, 2017 at 2:35 pm

    In Minesweeper on XP, using Win-D would show the desktop, but also stop the clock on the game. My shortest time for all the levels were one second.

    • Tina Sieber
      February 3, 2017 at 6:15 pm

      Ha, didn't know about that bug. Thanks, Nick!

  2. Michal Procházka
    January 5, 2017 at 2:19 pm

    The notepad bug also works in Windows 10(using build 14393.576) if you type "Diskmark" (without quotes), copy it like a million times and then save it, if you open it again, you will see that "Diskmark" turned into "????".

    • Tina Sieber
      January 6, 2017 at 10:11 am

      Thank you for sharing that one, Michal!

  3. Connor
    October 17, 2016 at 6:33 pm
    • Tina Sieber
      October 23, 2016 at 10:59 am

      Isn't that what you expected, Connor? Or are you concerned about the product activation failed message on top?

  4. Anonymous
    May 18, 2016 at 10:40 am

    The winblows calculator is messed up. Only windows calculator will incorrectly calculate the sqrt of a number that when multiplied to itself results in a who integer number and not a floating point. This does not happen in Unix, Linx, OS2, and even Mac os10. Example 2x2=4, now this is NOT 2.1x2.1 or 1.99x1.99 No, it is exactly 2x2.... As mentioned above this happens with 2x2 or 3x3 or 4x4, etc.... sqrt of 2 whole numbers will result in a whole number and not a floating point. Even entering 2.0000x2.0000 = 4.... Every calculator I own, from a Casio to a Texas Instruments all correctly calculate the value of sqrt numbers correctly, hence sqrt(4)=2, not 1.99999.... and when you enter sqrt(4)-2 you get 0 the correct answer. This is validated. In scientific mode you get 0e0, and in engineering mode you also get 0e0, now Texas Instruments cannot be incorrect in this mathematical calculation can they? After all we tried it in normal, scientific, and engineering mode and all of them gave the correct answer of 0 when entering sqrt(4)-2. I would agree to the floating point if in normal mode the sqrt(4)-2=0, but if enabling floating point calculations by going into scientific mode or engineering mode the answer to sqrt(4)-2=-1.0682.... I would then agree that the sqrt(4) is a floating point answer, but this is not the true answer unfortunately. You can even test this by putting the calculators into scientific mode and engineering mode, (Try it on any TI-89, TI-99, etc)

    Now here is the fabulous world of Microsoft, they do not think the same, they think the sqrt(4)=1.999999 and claims the answer is always a floating point number(the number i posted is not exactly what they have as an answer, I am just making an example so please refrain from posting there answer).... Now if you type in there crapulator sqrt(4)-2 you would think that due to the facts, the logical true answer would be 0 correct? They do not see that fact though and claim the answer is -1.068281969439142e-19(in standard mode) and . -8.1648465955514287168521180122928e-39(in scientific mode).... here is where they are flawed even more. I will explain why. If in standard mode the answer was -1.068281969439142e-19, then it will also be that same number in scientific mode. Again, verifiable on all TI calculators by just entering a number that cannot be obtained by multiplying two whole numbers like 2x2 or 3x3... etc. Try sqrt(5) just for an example, you will receive the exact number in normal mode, scientific mode, and engineering mode, one being a longer floating point though, but the answers are the same in either case. Even in Winblows Crapulator it will correctly display that. And if that was a different value in each mode it would have displayed it just the same. But Winblows Crapulator does not report back the same values when in standard or scientific mode when calculating the sqrt(4)-2, it thinks the answer is different in standard mode then it is in scientific mode, and they stick to this answer as being the true answer..... That is just downright crazy.

    Now for the ones that believe that Microsuck Winblows Crapulator is correct and not flawed, and that Microsuck is never wrong here... Just do some astronomical mathematics.... that is the proof you will ever need..... after all 0.000001 and 0.00001 or 0.0000001 will result in a telescope RA-DEC position to be way off, like by billions if not trillions of light years. If you think i am joking and just blowing smoke out my rear, just go buy you a Celestron NexStar 130SLT, or any other telescope with computer tracking will do, even manual tracking will work but just harder to precisely track a celestial body. Just use Microsucks Winblows Crapulator to do the calculations for locating a celestial body, find one that will need sqrt numbers that are whole and not floating point to locate and track. There are plenty of them out there, the NGC2000 book has hundreds of pages of them. Try it and come back and tell me if you were able to correctly locate and track anything. Good Luck...

    P.S. At the Panter Hall Observatory(Located in Austin Texas at the UT campus) the students and also the staff do not use any of the Microcrap Winblows Crapyalaters, We use things like the Texas Instruments, or Casio, or even some cheep ass dollar general calculator that is more accurate then the Slopware that Microphuck Wankerblows Crapavaders was made with. The answer they produce has never been incorrect, EVER, unless the wrong answer was a result of human error entering data incorrectly.

    There... I am done... Proof was shown...

    • eterni
      April 5, 2017 at 2:07 am

      The problem with Windows Calculator was totally caused by programmer's laziness / incompetence. The square root function that they wrote always give approximate value for every numbers, even though numbers such 1, 4, 9, 16, ... should give whole number.
      When they display 2 as the square root of 4, it's not really 2, it's a number that's smaller than 2, but almost 2. That's why when we substract 2 from it, it resulted in negative number.

      Even Windows 10 calculator still produce this result. They didn't bother to rewrite their square root function. They use legacy code from two decades ago.

      • Tina Sieber
        April 5, 2017 at 2:26 am

        Thank you for the explanation, Eterni!

    • Alex
      May 30, 2017 at 8:13 pm

      Wow, you ARE a real blow hard, aren't ya?! That post just got worse and worse over time, and by the end you sound like a dyslexic *beep*. Get off your high horse 'cos even though MS could have done better, you really don't have a clue about binary and floating point representation despite all your big talk about TI's calcs, astronomy etc.

  5. Havan
    March 27, 2016 at 11:57 am

    Just to provide an explanation for the calculator thing... Computers understand only binary (base 2). And the kind of math that humans find easier is decimal (base 10) (since we were born with 10 fingers and all that). Unfortunately, if a decimal terminates in base 10, it may be a non-terminating decimal in base 2, and hence is approximated. For eg, 1/10 in base 10 is just 0.1, but in base 2, it's something like 0.000110011001100110011... i.e. recurring. If you approximate this off to the first 9 digits, it results in 1/16 + 1/32 + 1/256 + 1/512.... = 0.099609375. This is true for a lot of numbers, which results in the kind of "error" you have talked about.

    P.S. Nice article :)

    • Alex
      May 30, 2017 at 8:15 pm

      Good explanation, Havan, unlike the incoherent ranting of the fellow above who likes to pretend on the interwebs that he's some sort of astronomer or something.

  6. kendall
    January 4, 2016 at 9:20 pm

    Hey guys i am running windows ten with word 2010 and i typed it in and it came up with around five paragraphs about the insert tab.What is that for?

  7. Larry
    March 3, 2015 at 4:25 pm

    The problem with the calculator is a bug that microsoft forget and it's totally normal!!!

    you should remain from commenting on computer science if you don't know anything about it!!

    In every math calculator, only the software can show up the correct decimal value.

    See IEEE754 for to understand how math chip are working!!!
    that something as a programmer I do know!! I'm a specialist, obviously, not you!!

    • Tina
      March 5, 2015 at 1:28 pm

      Thank you for weighing in, Larry. Glad you're here to educate us.

      As you correctly pointed out, I'm not a computer science or math specialist. My specialty is writing and editing. Of course, we all try our best and make mistakes. It's human, you know? :)

      By the way, the calculator issue persists in Windows 10. Must be hard to fix!

    • Eric Stoick
      February 8, 2016 at 3:41 pm

      Your also a douche, obviously!!!

      • Alex
        May 30, 2017 at 8:16 pm

        Only a real douche doesn't know the basic difference between "you're" and "your".

        P.S. Larry got it absolutely right.

  8. Tejas Dc
    May 21, 2011 at 5:11 pm

     the calculator bug holds good for sqrt of any number minus the answer..
    ex:sqrt16 - 4 , sqrt36 - 6  , sqrt81 - 9 all gives random results..

    • Tina
      May 21, 2011 at 6:19 pm

      Thanks for the update, Tejas!

  9. Aibek
    May 15, 2011 at 10:38 am

    great article!

  10. Kartik
    May 14, 2011 at 1:45 pm

    type Q33N in notepad and change the font to  size to 72 and font to wingdings
    you will see the secret about world trade center attack.

  11. JD
    May 14, 2011 at 7:43 am

    Haha that weird result from the calculator doesn't only happen "virtually". Some real scientific calculators don't even know how to subtract specific numbers...

    Neat article!

    • Tina
      May 15, 2011 at 12:21 pm

      That's pretty messed up.

  12. Anonymous
    May 14, 2011 at 1:58 am

     As for naming & renaming folder, when I type in "con/prn/lpt1/lpt2/com1/com2 & other reserved device name", what I get is just "New Folder" folder without name. The dialog box does not even appear.

    • Tina
      May 15, 2011 at 12:21 pm

      Might be different depending on the Windows version or edition. I took the screenshot in Windows 7 Professional.

  13. Jack Cola
    May 14, 2011 at 12:17 am

    If you like these Easter Eggs, Google also has a few Easter Eggs to look at too.

    Google Translator - http://www.jackcola.org/blog/128-the-best-google-translator-easter-eggs

    Google - http://www.jackcola.org/blog/128-the-best-google-translator-easter-eggs

  14. Anonymous
    May 13, 2011 at 3:21 pm

    Good thing I mostly use Linux. I only need Windoze for Netflix.

  15. Sahil Dave
    May 12, 2011 at 2:07 pm

    i was saving a image of chromes about:about by the name of "Chrome about:about" and it showed me the error that the file cannot be saved by this name...i checked with different options contain : but nothing work... i guess it happens as it'd bug cmd while changing directory and all...

  16. RichieB07
    May 12, 2011 at 12:17 am

    For the calculator trick, it seems to do that with any square root that you subtract the answer from. If you take anything like square root of 25 minus 5, square root of 16 minus 4, etc. it does that weird random answer.

  17. Anonymous
    May 7, 2011 at 2:08 pm

    The notepad bug can still be faked in win7: save it as ANSI, and then in the Open... screen, choose Unicode.

  18. Mike
    May 6, 2011 at 11:58 am

    Wikipedia also has a detailed explanation of the "CON" device bug.
    http://en.wikipedia.org/wiki/Concon

    On prior Windows version directly accessing a path like C:concon or C:connul would even crash your system because Windows would ignore the initial path identifier and try to access the device directly.

  19. Scutterman
    May 6, 2011 at 11:53 am

    I'm not sure if it works on W7 but on XP if you set your screensaver to marque "Who Cares?" and left it a month then it would change to "I do".

    • Christian
      May 6, 2011 at 3:49 pm

      Lol XD

    • Tina
      May 6, 2011 at 4:01 pm

      That's awesome!!!

  20. Bruce Epper
    May 6, 2011 at 7:56 am

    The algorithm that MS uses to calculate the square root of a number will almost always result in somewhat inaccurate results (1x10^-19 for 32-bit systems and 8x10^-39 for 64-bit systems). Since Calculator does not display 20 digits, it rounds the result to 2, but it maintains the calculated result for further use. Thus, when you subtract 2 from the result, you are not subtracting it from 2 but from 1.9999999999999999998931718030560858 (approximately) on a 32-bit system.

    This rounding error tends to be introduced when attempting to perform binary calculations on decimal numbers. It happens when the number systems don't have common boundaries (binary & hexadecimal have these common boundaries, but the decimal system does not share common boundaries with either of them).

    • Tina
      May 6, 2011 at 8:14 am

      Thanks a lot for the explanation, Bruce! :) That makes a lot of sense.

      • PSK
        May 10, 2011 at 11:40 am

        but then what about any other calculation with regards to square root of 4? like squrt(4)+1 gives 3 and not any other number. its only squrt(4) -2 which gives wierd numbers. :/

        • Tina
          May 10, 2011 at 11:57 am

          Good point. Maybe they forgot to correct the algorithm mistake in this case. Or it's intentional, say a reminder to never trust a computer 100%? Could be humor.

    • Eric Darchis
      May 6, 2011 at 1:51 pm

      In this specific case, it's an issue with the square root algorithm indeed. But usually, this kind of error is due to "floating point" representation. We express a number in 1.234*10^45 while the computer will have 3.46383349*2^79. The computer uses powers of 2 rather than powers of 10. This means that rounds numbers in decimal might not be round in binary. That's why the approximation errors can sometimes propagate and become visible.

      Here, we have 4 which is a round number and its square root is a round number in binary too, so it should work.

      I have seen a case where this kind of problem ended up costing thousands of dollars in the company billing system.

  21. Saikat Basu
    May 6, 2011 at 4:49 am

    Does anyone know about the 'Clock' animation file that can be found under
    My ComputerC:WINDOWS. It's a relic in Windows XP. Not sure if it's still their in Vista and 7.

    • Tina
      May 6, 2011 at 8:16 am

      I don't. What is the file called and where is it located in Windows XP? I have Windows 7, curious whether it's still there.

      • Scutterman
        May 6, 2011 at 4:59 pm

        It used to be "clock.wmv", I don't think it's included any more.

        • MPoppers
          May 13, 2011 at 3:29 pm

          I have C:WindowsCLOCK.AVI on my WinXP desktop. 

        • Scutterman
          May 14, 2011 at 7:56 am

          Yeah, I remember it as AVI now too. It's not in the Windows folder in W7 though.

  22. Anonymous
    May 6, 2011 at 1:47 am

    If I recall correctly, the "Bush hid the facts" bug works for any sentence with four words in a four-three-three-five letter scheme.

    • Adhar Srivastava
      May 13, 2011 at 6:03 pm

       u indeed recall correctly

  23. Me
    May 6, 2011 at 1:38 am

    I just did it with Word 2011 for Mac and I got the sentences.

    • Dan
      May 6, 2011 at 3:04 am

      Heh, goes to show that the Mac team at MS Office is still at the pre-2007 stage feature-wise.

    • Aa
      July 20, 2011 at 6:12 pm

      that's it just working

  24. Dan
    May 6, 2011 at 1:16 am

    Whoa, are you still on Word 2003? I know Word 2007 and 2010 does not use that sentence any more.

    • Sahil Dave
      May 6, 2011 at 4:29 am

      i did on word 2010 and it gave 5 paragraphs about Insert tab !!

      • Tina
        May 6, 2011 at 8:13 am

        Thanks for sharing what it does in Word 2010!

      • Rachelle
        May 15, 2011 at 4:39 am

         I got paragraphs about the insert tab and galleries in Word 2007 as well. I think that Word help files are lonely and this is a ruse to try to get someone to read them. I fell asleep after the first 4 words though.

    • Tina
      May 6, 2011 at 8:12 am

      Have to admit that I was on Word 2003 until I updated to Windows 7 recently. Now I don't use Word anymore and I can tell you that this doesn't work in LibreOffice. :)

  25. Maninblack4xp
    May 6, 2011 at 3:13 am

    More eggs {xp} can be found here...

    http://home.comcast.net/~Suppo...

  26. Maninblack4xp
    May 6, 2011 at 1:13 am

    More eggs {xp} can be found here...

    http://home.comcast.net/~SupportCD/XPSecrets.html

  27. Elijah Love
    May 6, 2011 at 12:30 am

    Win7 Home Premium 64-Bit: -8.1648465955514287168521180122928e-39

    • Ray Herring
      May 8, 2011 at 1:57 am

      Win7 Home Premium 64-bit: -1.068281969439142e-19

      Probably depends on Locale too, dunno, mine is English Australian

      • Todd Makeuseof
        May 13, 2011 at 5:57 pm

         The result changes with the view you have set on the calculator.

    • Adhar Srivastava
      May 13, 2011 at 6:01 pm

       32-bit too

    • Bruno Fischer
      May 6, 2015 at 1:07 pm

      Hi. This is not exactly a bug. This type of surprising results will happen if you compute the difference of two numbers which are almost identical:
      As a rule, the square root of a number cannot be computed exactly. A program determines an approximate value for any square root. here, the square root of 4 was found to be almost 2, and was displayed as 2, but the stored value was not exactly 2, so, of course the difference with 2 yield the rounding error: a 0.0000....(put here 18 zeroes)...1068....
      Rounding errors are worse when substraction is used on large numbers, on a system which represents number as Floats, which means all mainstream computer programs.
      Avoiding this necessitates the use of structures called BIGNUMS in Lisp/Scheme...
      This is the reason why the equality of two non-integer numbers a and b should never be tested with the test "b-a=0", but with something like "b-a<e" , where e is the maximal admissible rounding error.