Low Coupling

Two elements of the system are coupled if one of them uses, contains knowledge about, or depends on the other element. The depended element can be forced to react on the changes in element which he depends on. For example, derived classes are highly depended from their base classes. Another example is object A which invokes operations of object B – object A is depended on object B.

Low coupling is an pattern which we use to evaluate existing solutions or for choosing best one. If there are no any other circumstances we should choose this project which contains fewest number of dependences ( in other words it has lowest coupling)