Namespaces give you one mechanism to modularize code. A namespace allows you to label your types, functions, and variables with a unique name so that, using the scope resolution operator, you can give a fully qualified name. The advantage is that you know exactly which item will be called. The disadvantage is that using a fully qualified name you are in effect switching off C++'s argument-dependent lookup mechanism for overloaded functions where the compiler will choose the function that has the best fit according to the arguments passed to the function.
Defining a namespace is simple: you decorate the types, functions, and global variables with the namespace keyword and the name you give to it. In the following example, ...
