Definition: Loose coupling

Coupling is the measure of the degree of interdependence between modules in a software. A rule of thumb is that good software will have loose or low coupling.

Loose coupling ensures that each module or component in a software has, or makes use of, little to no knowledge of the definitions of other separate components or modules. In other words, loose coupling is about separating unrelated parts of the code base as much as possible. This makes software more maintainable and extensible.

A good software generally employs high cohesion and ​loose coupling.