In computing

Computing

Computing is usually defined as the activity of using and improving computer hardware and software. It is the computer-specific part of information technology...

, a fatal error or fatal exception error is an error

Error

The word error entails different meanings and usages relative to how it is conceptually applied. The concrete meaning of the Latin word "error" is "wandering" or "straying". Unlike an illusion, an error or a mistake can sometimes be dispelled through knowledge...

 that causes a program to abort and may therefore return the user to the operating system

Operating system

An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...

. When this happens, data that the program was processing may be lost. A fatal error is usually distinguished from a fatal system error

Fatal System Error

Fatal System Error is a nonfiction work written by Joseph Menn that exposes a story of espionage that penetrates the network of international mobsters and hackers who use the Internet to extort money from businesses, steal from tens of millions of consumers, and attack government networks.Its main...

 (colloquially referred to by the error message it produces as a "blue screen of death"). A fatal error occurs typically in any of the following cases:

• An illegal instruction has been attempted
• Invalid data
  Data
  The term data refers to qualitative or quantitative attributes of a variable or set of variables. Data are typically the results of measurements and can be the basis of graphs, images, or observations of a set of variables. Data are often viewed as the lowest level of abstraction from which...
  
   or code has been accessed
• An operation is not allowed in the current ring
  Ring (computer security)
  In computer science, hierarchical protection domains, often called protection rings, are a mechanism to protect data and functionality from faults and malicious behaviour . This approach is diametrically opposite to that of capability-based security.Computer operating systems provide different...
  
   or CPU mode
  CPU modes
  CPU modes are operating modes for the central processing unit of some computer architectures that place restrictions on the type and scope of operations that can be performed by certain processes being run by the CPU...
  
  
• A program attempts to divide by zero
  Divide By Zero
  Divide By Zero was a British video game developer. It was disestablished sometime in 1996.Divide By Zero is a BBS originally started in 1996 in Columbia SC by Keven and Eric Coots...
  
  . (Only for integers; with the IEEE floating point
  Floating point
  In computing, floating point describes a method of representing real numbers in a way that can support a wide range of values. Numbers are, in general, represented approximately to a fixed number of significant digits and scaled using an exponent. The base for the scaling is normally 2, 10 or 16...
  
   standard, this creates an infinity
  Infinity
  Infinity is a concept in many fields, most predominantly mathematics and physics, that refers to a quantity without bound or end. People have developed various ideas throughout history about the nature of infinity...
  
   instead)

In some systems, such as Mac OS X

Mac OS X

Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems...

 and Microsoft Windows

Microsoft Windows

Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...

, a fatal error causes the operating system to create a log entry or to save an image (core dump

Core dump

In computing, a core dump consists of the recorded state of the working memory of a computer program at a specific time, generally when the program has terminated abnormally...

) of the process.

External links

• Fatal exception error - Webopedia
• What Are Fatal Exception Errors - Microsoft Knowledge Base