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Magic Number

What Does Magic Number Mean?

The term “magic number” in IT has several meanings. Perhaps most prominently, magic numbers are constants or static numbers that are insufficiently declared in a program, or hidden within source code. Some definitions of “magic number” are linked to the use of the UNIX operating system and its use of memory addresses.


Techopedia Explains Magic Number

Experts often describe magic numbers as strongly typed data objects. One description of a magic number is a constant that is not defined using a commented piece of source code, but that is just stuck in the program implicitly. In some cases, magic numbers lead to numeric overflows and runtime errors. They may have a negative effect on algorithm functionality. While there are a variety of slang uses for the term “magic number,” the general idea is that these numbers have some particular significance, either in the limitations of an operating system, their impacts on a software program, or some other meaning.


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