Programming languages and paradigms
- 2. First Generation: Machine Languages The late 1940s to early 1950s saw the emergence of first generation languages (1GL). They are known as machine languages and use a binary code that consists of strings of only zeroes (0) and ones (1). These are languages that are computer can understand and execute directly without any need for translation. Programs written in 1GL relatively run quickly and efficiently.
- 3. Second Generation: Assembly Languages In the early mid-1950s, second generation languages (2GL) came out. They usually refer to some form of symbolic or assembly language – instead of zeroes and ones, assembly languages use mnemonics or very short words for commands. Compared to 1GL, 2GL is a little less difficult for programmers to learn and use. 1GL and 2GL are both low-level languages. They are designed to facilitate fast and efficient execution in computers, without much regard for the convenience of the programmers who use them
- 4. Third Generation: High-Level Languages Third generation languages (3GL), also called high-level programming languages, began to unfold during the mid – to late 1950s. With developments in computer hardware during this period showing a trend towards a rapid increase in computing power, developments in programming languages started to shift towards a high-level language. Most modern computer languages belong here. 3GL introduced the use of data structures and control structures, which are high-level abstractions of programming concepts that previously had to be coded directly in low-level languages.
- 5. Fourth Generation: Declarative Languages Despite the improved capabilities of 3GL, programming continued to be a slow, frustrating, and error-prone process. The amount of programming work soon exceeded the amount of time available for the programmers to do it. Fourth generation languages (4GL) are more advanced than traditional high-level programming languages. Commands are usually English-like and do not require traditional input- process-output logic. They are also referred to as non-procedural specification languages – a programmer who writes 4GL programs concentrates more on what needs to be done rather than how to do it.
- 6. Fifth Generation: AI (Artificial Intelligence) Fifth generation languages (5GL) are basically an outgrowth of artificial intelligence research from the 1980s. Conventional Languages then rely on algorithms defined by the programmer to solve problems; the approach is to build a program that implements a specific algorithm devised by the programmer to address a specific problem. 5GLs operate on the concept of solving problems based on constraints or rules that have been declared in the program.
- 7. COMPUTER HARDWARE EVOLVED THROUGH SIMILAR GENERATIONS 1st Generation – Vacuum tubes 2nd Generation – Transistors 3rd Generation – integrated circuits (ICs), small-scale integration (SSI), medium-scale integration (MSI) 4th Generation – large-scale integration (LSI), very large-scale integration (VLSI) 5th Generation – Parallel processing architectures 6th Generation – Massively Parallel architectures, parallel/vector architectures
- 8. IMPERATIVE PROGRAMMING Imperative Programming is the oldest and most traditional model of computing. In a regular, non-programming context, the word “imperative” refers to a mood essential order or command. Here, it describes computation in terms of a program state and the actions that change that state. Imperative languages evolved from machine and assembly languages, whose characteristics reflect the principle of the von Neumann architecture. The program consists of explicit command or instruction to be executed
- 9. VON NEUMANN ARCHITECTURE is the design upon which many general purpose computers are based. The key elements of von Neumann architecture are: data and instructions are both stored as binary digits. data and instructions are both stored in primary storage.
- 10. EXAMPLES OF IMPERATIVE PROGRAMMING • Ada • Fortan • Basic • Algol • Pascal • Cobol • Modula • C
- 11. FUNCTIONAL PROGRAMMING Functional programming is an expression-oriented programming paradigm. Computations are specified through mathematical function that evaluate input expressions and convert them into output values. Functional programming languages are “what” –oriented.
- 12. EXAMPLES OF FUNCTIONAL PROGRAMMING • Lisp • Scheme • FP • Standard ML • Haskell
- 13. LOGIC PROGRAMMING In the logical paradigm, programs are written as logical statements that describe the properties the solution must have. The program is viewed as a logical theory and computation is basically the search for proof. It may also be stated the logic programming is based on the concept of logical deduction in symbolic logic, or the manipulation of symbols.
- 14. EXAMPLES OF LOGIC PROGRAMMING • Prolog • Lambda Prolog • CLP • PICAT
- 15. OBJECT-ORIENTED PROGRAMMING In object-oriented programming, data structures are viewed as objects, and programmers create relationships between these objects. A group of objects that have the same properties, operations and behaviors is called a class. By reusing classes developed for the applications, new applications can be developed faster and with improved reliability and consistency of deisgn
- 16. EXAMPLES OF OBJECT-ORIENTED PROGRAMMING • Smalltalk • Simula • Java • C++
- 17. CONCURRENT AND DISTRIBUTED PROGRAMMING Concurrent or parallel programming is a computer programming technique that allows for the execution of two or more operations at the same time. Conventional paradigms deal with programming operations in linear fashion that is from start to finish and in one continuous execution. The idea in concurrent programming is to split a single task into several smaller subtask that can run relatively independently of each other
- 18. CONCURRENT AND DISTRIBUTED PROGRAMMING Parallel programming is effective mainly for programming problems that can be readily broken down into independent subtasks, such as certain mathematical problems like factorization. It can be implemented on a single computer, or across a number of computers. When a multi-processor or multi-computer platform is used to implement this, we use the term Distributed programming.
- 19. EXAMPLES OF CONCURRENT AND DISTRIBUTED PROGRAMMING • Parallel Pascal • Concurrent ML