A term with a variety of meanings. For example, the “implementation” of a component describes how it is constructed; thus, a primitive implementation describes a component implemented by some source document—the source code of a programming language, scripts of commands for an operating system shell, or data in a file in the file system. The implementation of a primitive component, therefore, consists of a list of implementation variants—or alternative implementations. So, if a component has more than one variant defined in its primitive implementation, the specific variant to be used during system construction can be selected using the variant property. In short, a variant definition consists of a name, a pointer to a file in the operating system containing the source document that implements it, and properties that further specify the variant.

Moreover, next-generation versions of worms and viruses are often referred to as variants of the base type. Virus numbering schemes reflect the notion of variants by giving viruses a base name and appending a letter or number to identify the variant, such as Sobig.a and Sobig.f.

See Also: Malware; Polymorphic Virus; Virus; Worm.