Click on one of the magic numbers below to print it on the shirt.
0x0000000FF1CE ("office") is used as the last part of product codes (guid) for Microsoft Office components (visible in registry under HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall registry key).
0x00BAB10C ("über (ooba) block") is used as the magic number for the ZFS uberblock.
0x8BADF00D ("ate bad food") is used by Apple in iOS crash reports, when an application takes too long to launch, terminate, or respond to system events.
0x1BADB002 ("1 bad boot" ) Multiboot header magic number.
0x1CEB00DA ("ice buddha") was used as the origin for the binary file parser IceBuddha.
0xB105F00D ("BIOS food") is the value of the low bytes of last four registers on ARM PrimeCell compatible components (the component_id registers), used to identify correct behaviour of a memory-mapped component.
0xB16B00B5 ("big boobs") was required by Microsoft's Hyper-V hypervisor to be used by Linux guests as their "guest signature". One proposal suggested changing it to 0x0DEFACED ("defaced"). Actually, it was initially changed to decimal and then replaced entirely.
0xBAADF00D ("bad food") is used by Microsoft's LocalAlloc(LMEM_FIXED) to indicate uninitialised allocated heap memory when the debug heap is used.
0xBADDCAFE ("bad cafe") is used by Libumem to indicate uninitialized memory area
0xCAFEBABE ("cafe babe") is used by Mach-O to identify Universal object files, and by the Java programming language to identify Java bytecode class files. It was originally created by NeXTSTEP developers as a reference to the baristas at Peet's Coffee & Tea.
0xCAFED00D ("cafe dude") is used by Java as a magic number for their pack200 compression.
0xCEFAEDFE ("face feed") is used by Mach-O to identify flat (single architecture) object files. In little endian this reads FEEDFACE, "Feed Face".
0xD15EA5E ("disease") is a flag that indicates regular boot on the Nintendo GameCube and Wii consoles.
0xDABBAD00 ("dabba doo") is the name of a blog on computer security.
0xDEADBAAD ("dead bad") is used by the Android libc abort() function when native heap corruption is detected.
0xDEADBABE ("Dead Babe") is used by IBM Jikes RVM as a sanity check of the stack of the primary thread.
0xDEADBEAF ("dead beaf") is part of the signature code of Jazz Jackrabbit 2 tileset files. Level files have less room for their signatures and use 0xBABE ("babe") instead. It is also the header of campaign gamesaves used in the Halo Game Series.
0xDEADBEEF ("dead beef") is frequently used to indicate a software crash or deadlock in embedded systems. DEADBEEF was originally used to mark newly allocated areas of memory that had not yet been initialized—when scanning a memory dump, it is easy to see the DEADBEEF. It is used by IBM RS/6000 systems, Mac OS on 32-bit PowerPC processors and the Commodore Amiga as a magic debug value. On Sun Microsystems' Solaris, it marks freed kernel memory. On OpenVMS running on Alpha processors, DEAD_BEEF can be seen by pressing CTRL-T. The DEC Alpha SRM console has a background process that traps memory errors, identified by PS as "BeefEater waiting on 0xdeadbeef".
0xDEADC0DE ("dead code") is used as a marker in OpenWrt firmware to signify the beginning of the to-be created jffs2 filesystem at the end of the static firmware.
0xDEADDEAD ("dead dead") is the bug check (STOP) code displayed when invoking a Blue Screen of Death either by telling the kernel via the attached debugger, or by using a special keystroke combination. This is usually seen by driver developers, as it is used to get a memory dump on Windows NT based systems. An alternative to 0xDEADDEAD is the bug check code 0x000000E2, as they are both called MANUALLY_INITIATED_CRASH as seen on the Microsoft Developer Network.
0xDEADD00D ("dead dude") is used by Android in the Dalvik virtual machine to indicate a VM abort.
0xDEADFA11 ("dead fall") is used by Apple in iOS crash reports, when the user force quits an application.
0xDEAD10CC ("dead lock") is used by Apple in iOS crash reports, when application holds on to a system resource while running in the background.
0xDEADFEED ("dead feed") is used by Apple in iOS crash reports, when a timeout occurs spawning a service
0xDEFEC8ED ("defecated") is the magic number for OpenSolaris core dumps.
0xE011CFD0 is used as a magic number for Microsoft Office files. In little endian this reads D0CF11E0, "docfile0".
0xFACEFEED ("face feed") is used by Alpha servers running Windows NT. The Alpha Hardware Abstraction Layer (HAL) generates this error when it encounters a hardware failure.
0xFBADBEEF ("bad beef") is used in the WebKit and Blink layout engines to indicate a known, unrecoverable error such as out of memory.
0xFEE1DEAD ("feel dead") is used as a magic number in the Linux reboot system call.
0x4B1D ("Forbid'den'") was a password in some calibration consoles for developers to peer deeper into control registers outside the normal calibration memory range.
Computer programmers have a special sense of humor that is often manifested in source code. One example of this kind of humor are magic numbers that can be read as hexspeak words like the ones above. Magic numbers like these are often used as debug values in computer processors and operating systems.
Information on these magic numbers is from the Wikipedia article about Hexspeak.
This post was written by Ramiro Gómez (@yaph) and published on (updated: ). Ramiro is a developer who likes open source, data mining, visualization and writing. To be informed about new posts you can subscribe to the Geeksta RSS feed.
External links on this website may contain affiliate IDs, which means that I earn a commission if you make a purchase using these links. This allows me to offer hopefully valuable content for free while keeping this website sustainable. For more information, please see the disclosure section on the about page.