The World of Programming Paradigms

 

The World of Programming Paradigms

First of all, let’s know about what a computer program is. You all know a computer program is a set of instructions that are arranged in a structured way. It performs specific tasks when it is executed by the computer. According to history, with the Von Neumann computer architecture, the stored program concept was introduced. Actually, it is the inception of modern computers. In the early stages, programmers used machine language to write programs (binary) that can be directly understood by the computer. However, with the expansion of user needs it is very hard to write with machine language. To solve that problem machine language emerged. But after years of time, it became very difficult to debug programs in assembly language. With time programmers tried to find better solutions for these problems.    

What is a paradigm?

Let’s clarify this using an example. A long time ago, scientists thought that there are only atomic particles and they can’t divide furthermore. But after years and many experiments, they discovered that there are also subatomic particles existing in nature. When looking at this example we can identify that atomic theory is one paradigm and subatomic theory is another paradigm. In this case, atomic theory shifted to subatomic theory. Now you can understand paradigm is a set of interrelated theories, perceptions, concepts, and practices within the community about a subject at a particular time, it is a set of generally accepted scientific achievements and models that defines how to look at problems and how to solve them. With the time, community starts to criticize it and emerge a new paradigm. This process is known as a paradigm shift. This shifting takes a long time to change with the understanding drawbacks of exiting system.

 

1.         1. Programming paradigms 

A programming paradigm is a way to classify programming languages according to their features and ways of performing tasks. Programming languages can be classified into multiple paradigms. However, mainly two different paradigms are evolved with time.

 

1.1  Imperative Programming paradigm-

·         Oldest and most traditional paradigm in the world.

·         Developed with the emergence of the machine and assembly language.

·         Main feature is a sequence of explicit commands.

·         User must write the command correctly and feed it into the computer.

 

1.1.1        Procedural Programming

·    Basic concept of the procedural call.

·    Contain a series of computational steps to be carried out.

·    Examples are FORTRAN, ALGOL, COBOL, PL/I, and BASIC.

 

1.1.2        Object-Oriented Programming

·    Based on the concept of ‘objects’ which can contain data and code.

·  Computer programs are designed by making them out of objects that interact with one another.

·   Some Object-Oriented languages are Java, C++, C#, Python, R, PHP, VB.NET, JavaScript, Ruby, Perl, SIMSCRIPT, Object Pascal, Smalltalk, MATLAB, etc.

 

 

1.2  Declarative programming paradigm.

·         Focus on the end result.

·         Can be divided into two types.

 

1.2.1    Functional Programming Paradigm

·    Programs are constructed by applying and composing functions.

·   Function definitions are trees of expressions that map values to other values rather than a sequence.

·    Functions are treated as first-class citizens.

 

1.2.2    Functional logic programming language

· Designed to handle symbolic computation and list processing applications.

·    Includes both functional and logical concepts.

·  Popular functional programming languages are Lisp, Python, Erlang, Haskell, Clojure, etc.

 

2.      2. Database management language paradigm 

This is a type of declarative programming language for creating and controlling database systems. Mainly there are two kinds of paradigms.

           

            2.1     Structured Query Language (SQL)

The relational database includes tables, relations between tables, and schemas. A few examples of the SQL languages are MySQL, MS SQL Server, Oracle.

           2.2      NoSQL

NoSQL has a dynamic schema for unstructured data, and data is stored in many ways. NoSQL can create documents without having to first define their structure and each document has its own unique structure. The syntax can vary from database to database.

 

 

3.      3. Object-Oriented Programming Paradigm

 

OOP is derived from the imperative paradigm and OOP concepts. OOP is not a language. A feature of objects is that an object's own procedures can access and often modify its data fields. OOP is writing programs considering objects and their relationships. Template for and object in programming is called class.

 

 

4.    4. Parallel Programming

Running Programs simultaneously with a multi-processor has less processing time than running programs with a single processor. Using parallel programming in C is important to increase the performance of the software.

Kalana Minipuraarachchi

BSE(UG) OUSL