Computer Architecture influences Language Design:

• Von Neumann Computer Architecture


        - Data and programs stored in the memory. 
          - Memory is separate from CPU
        - Instructions and data are piped from memory to CPU
        - Features of Imperative Language: using variables to do assignment statements. Also, iteration is efficient
        - Example of Imperative Language:  Fortran, Pascal, Cobol, C,.....
 

• Functional Language is not as fast as Imperative Language.

        - There is no variable in Functional Language.
 
• Parallel Architecture:  try to speed up functional programs.

• 1950s and early 1960s: Simple applications; worry about machine efficiency
• Late 1960s: People efficiency became important; readability, better control structures
  • structured programming
  • top-down design and step-wise refinement
• 1970's     Top down design and stepwise refinement  

               get rid of   GOTO ,      use DO/WHILE
               Process - Oriented
 
• Late 70's shift to data-oriented method 

Abstract Data Type      (encapsulate)
 
• 1980's     Object-Oriented Design 

               inheritance and dynamic type binding
                    Data abstraction + inheritance + polymorphism
               Compare Smalltalk with C++ in chapter 11