Every nonzero finite-dimensional inner product space has an orthonormal basis. It makes sense when you don't think about it.
|--Math Professor, U.C. Berkeley|
Classes and interfaces can be declared inside other classes and interfaces, either as members or within blocks of code. These nested classes and nested interfaces can take a number of different forms, each with its own properties.
The ability to define nested types serves two main purposes. First, nested classes and nested interfaces allow types to be structured and scoped into logically related groups. Second, and more important, nested classes can be used to connect logically related objects simply and effectively. This latter capability is used extensively ...