The so-called Blue Screen of Death, also written as BSoD for short, refers to the screen displayed by Microsoft's Windows operating system when it cannot (or is in danger of being unable to) recover from a system error.
The Windows NT operating system's kernel generally cannot recover from the error, and the only action a user can take is to restart the operating system, losing all unsaved work and possibly breaking the consistency of the file system. The information displayed on the Blue Screen of Death is useless to NT users without access to the Windows source code. Microsoft's desktop operating systems Windows 95, 98, and ME, also at times indicate problems with a display of somewhat cryptic information on what has also come to be called the Blue Screen of Death. However, these screens give the user some options, some with a hope of continuing, and thus this is also referred to simply, and perhaps more properly, as just a "blue screen"--the "death" of the operating system is not always imminent.
By default, the display is white (CGA color 0x0F; HTML color #FFFFFF) lettering on a blue (EGA color 0x01; HTML color #0000AA) background, with information about current memory values and register values.
Showing they have a sense of humor, Microsoft has added a utility that allows the user to change a setting in
system.ini that controls the colors that the BSoD code uses to any of the 16 standard CGA colors.
System adminstrators often use "to bluescreen" or "to BSoD" as a verb, as in: "The server just BSoDed" or "Windows 2000 doesn't bluescreen as much as NT 4 did." (This usage is unrelated to color key special effects in film, also called bluescreen.)
The Blue Screen of Death is extinct in the new Windows XP Professional OS. However, it is a feature of the following OS's:
- Microsoft: Windows 2
- Windows 3
- Windows 95
- Windows 98/se
- Windows ME
- All the NT range (excluding XP)