Loose Coupling

'''Loose coupling''' means low dependency between two [[System|systems]]. 
It is a way to achieve high [[Fault Tolerance|fault tolerance]]
and often used in association with [[Web Service|Web Services]] and [[Service-Oriented_Architecture|Service-Oriented Architecture (SOA)]].
Loosely coupled systems are not strongly connected with each other,
they have only a minimal coupling between the components in the system.
They are obviously the opposite of tightly coupled systems with
strong dependencies between the components.
In loosely coupled systems, there is a low probability that changes 
within one module or component will create unanticipated changes 
within other modules or components.
The modular approach to design and develop systems
associated with loose coupling makes the applications more 
agile and flexible, and enables quicker change.
A common way to achieve low coupling is to use interfaces
and messages: one module does not have to be concerned 
with the internal implementation of another module, 
and interacts with another module with a stable 
interface.

== References ==

[http://dev2dev.bea.com/pub/a/2004/02/orchard.html Achieving Loose Coupling], David Orchard