Concurrency and Communication Evolution in Computing

• Sequential computing (1940): a single instruction at a time is executed. • Imperative models: Turing machines and less expressive automata (finite-state automata, push-down automata). • Declarative models: Church λ-calculus, first-order logic. • Programming languages (Fortran, Cobol, Algol, C,..., Lisp, Prolog,...). • Concurrent and distributed computing (1980): several instructions can be simultaneously executed. • Shared-memory model vs. message-passing model. • Primitives for programs synchronization (semaphores, monitors,...). • Concurrent programming languages (Ada, Occam, Java,...). • Global computing (2000): computation over infrastructures available globally and able to provide uniform services with variable guarantees, with particular regard to exploiting their universal scale as well as the programmability of their services. • Development of large-scale general-purpose computer systems that hav