The object-oriented approach to programming and design is characterized by its focus on the data structures of a program rather than the procedures. Often, invoking a procedure with a data object as its principal argument is thought of as ‘sending a message’ to the object. Special language support is typically available for collecting these procedures (sometimes known as ‘methods’) together with the definition of the type of the object. This approach is supported in Fortran by type extension, polymorphic variables, type-bound procedures, abstract types, and finalization.
Data structures and algorithms: An object-oriented approach using Ada 95