A module is a piece of code that carries a name and is syntactically distinguished from other parts of the code.
Several principles deal with the decomposition and interaction of classes, methods, procedures, functions, etc. In order to abstract from the concrete syntactic element—be it a class, a method, a procedure, a function, an executable or the like—the term “module” is used. A module is a general concept of a distinguishable part of the code which can be represented by a variety of language constructs.
In the context of modular programming “module” refers to the concept of a specific part of a system encapsulating a certain piece of functionality.
In some programming languages “module” may refer to a certain language feature more or less linked to the module concept in modular programming (see above).
Discuss this wiki article and the term on the corresponding talk page.