Influences on Language Design
• Computer Architecture
– Languages are developed around the prevalent computer architecture, known as the von Neumann architecture
• Programming Methodologies
– New software development methodologies (e.g., object-oriented software development) led to new programming paradigms and by extension, new programming languages
Computer Architecture Influence
• Well-known computer architecture: Von Neumann
• Imperative languages, most dominant, because of von Neumann computers
– Data and programs stored in memory
– Memory is separate from CPU
– Instructions and data are piped from memory to CPU
– Basis for imperative languages
• Variables model memory cells
• Assignment statements model piping
• Iteration is efficient
Programming Methodologies Influences
• 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
• Late 1970s: Process-oriented to data-oriented
– data abstraction
• Middle 1980s: Object-oriented programming
– Data abstraction + inheritance + polymorphism