Python vs. JavaScript: The 11 Major Differences

Stack Overflow (a question-answering platform for software professionals and developers) surveys more than 100,000 software developers annually to identify programming trends, job opportunities, and challenges.

In a survey in 2018, they found out that Python was the most popular programming language among the developer community. 25.1% developers wanted to learn it and increase their programming skills. JavaScript ranked second after Python with a 19% popularity rate.

In this article, I explore 11 major differences between the Python and JavaScript programming languages.

Table of Contents

You can skip to a specific section of this Python vs. JavaScript analysis using the table of contents below:

Python Overview

Python is a high-level object-oriented programming language. It allows developers to use built-in data structures, combined with dynamic binding and typing.

Python is a scripting language like Perl, PHP, and Ruby that allows you to create desktop and web applications.

Python ranks second after R as one of the widely-used programming languages for data science and statistical analysis - especially machine learning. It’s an open source language providing optimized features for code readability, programmer productivity, and software quality. Python is diverse and allows developers to create a variety of programs ranging from simple to complex programs.

JavaScript Overview

JavaScript is a scripting language and, like other languages of this genre, it supports the purpose of making programming easier by automating websites and app features. It also supports object-oriented capabilities and is considered as one of the core web technologies (along with HTML and CSS). JavaScript typically provides dynamic functionalities in webpages that can’t be achieved just using HTML or CSS.

With the emergence of Node.js in 2009 (which serves as a backend language), the popularity of JavaScript has increased. Now developers can use JavaScript for both front-end and server-side development.

Python vs. JavaScript - Which Language is Better?

There is no direct and easy answer to this question. Both languages are very popular due to their powerful features. The purpose of this article is to help you understand their strengths and weaknesses to identify which one suits you the best and fulfills your purpose.

For the rest of this article, we'll discuss the 11 major differences between Python and JavaScript. Let's dig in!

1. Learnability

Learnability refers to the ease of learning. Learnability is very important when you are learning a new programming language (even with no prior programming experience).

Time is precious. You need to chose a programming language that is user-friendly and easy to learn with minimum effort.

From this perspective, Python has a short learning curve and you could learn it in a few months. Python is designed as a beginner-friendly language that provides more simple functions and variables.

On the other hand, the learning curve of JavaScript is a little steeper than other fundamental front-end languages such as HTML and CSS. I've been coding JavaScript for years and I still encounter new concepts regularly.

Overall, from a learning perspective, I would say that Python is the better choice.

2. Scalability

Scalability is an important feature of any programming language when it comes to developing applications. It is measured by two parameters: i) the ability to support a large number of users, and ii) its capacity of process number of transactions and data with a minimal server utilization.

Node.js provides the feature of handling asynchronous programming while Python does not support asynchronous programming. So, in terms of scalability, JavaScript ranks better than Python.

3. Data Science – Python or JavaScript?

Data science has been a hot area in software and web development for many years. The focus of data science is allowing developers to analyze, manipulate and understand raw or structured data and to make inferences based on that data.

JavaScript is a very powerful programming language; however, that doesn't mean that it would be best for every type of programming project.

Data scientists usually use one of two languages. Python is one of them (with the other being R).

Although JavaScript can technically perform data science tasks, data scientists usually prefer developing applications in Python due to its prevailing features for data science. Python was not originally designed for solving data science problems, but today it is one of the best languages for data science, machine learning, and predictive analytics.

Here are some reasons why:

  • Python provides a wide range of built-in frameworks and libraries that empower developers with thousands of useful functions. These frameworks and libraries not only help developers save time and write more performant code.
  • Some of the essential Python libraries for data science are Numpy, Pandas, Matplotlib, Scikit-Learn, and Scipy. JavaScript, on the other hand, doesn't have a robust ecosystem of data science libraries. Because of this, it is very difficult to perform good data science work in that language.
  • Visualizing data through different appealing charts or graphs is one of the core activities in data science. Python provides a list of libraries that allows you to create very appealing visualizations. Some of the top visualization libraries of Python include Matplotlib, Plotly, Seaborn, gplot, and Altair.
  • JavaScript, being a scripting language, was not originally designed for performing data science tasks. It does not perform these tasks efficiently and it take much more time to process data science algorithms applied to large data sets. On the other hand, Python performs can efficiently build and train complex data science models.

4. Inheritance

Like other object-oriented languages, Python supports inheritance. Inheritance allows base classes (child classes) to inherit objects and behavior from parent class (parent class). It uses a class-based inheritance model.

JavaScript uses a prototype-based inheritance model. This increases the complexity of JavaScript as a programming language. In this approach, all the objects inherit methods and properties from a prototype.

5. Function Arguments

If we talk about function parameters in both languages, we can also see a difference here. If a function is incorrectly called or provides a wrong number of parameters in Python, an exception with a custom message occurs at the time of function execution. This indicates that the developer doesn’t know the actual number of parameters until functioning calling.

JavaScript allows for a random and infinite number of arguments which can be accessed by an argument object. JavaScript also allows for correct and incorrect arguments. If a variable points to no object, then it is declared as undefined.

6. Mutability

Python contains mutable and immutable data types. Mutability allows change in content or state of an object after it is created. Immutable objects cannot modify their state after their creation. Examples of some mutable objects are set, list, and dict are whereas objects like int, tuple, bool, Unicode are immutable.

JavaScript, on the other hand, gives the developer the power to decide whether a variabel should be mutable or not. This is done through the use of the var, let, and const keywords.

JavaScript variables declared with var or let are mutable while variables created with const are not.

7. Need of an Interpreter

An interpreter is a program that directly interprets and executes a code written in a programming or scripting language without converting it into machine code.

Like other high-level programming languages, Python requires an interpreter to execute code.

JavaScript does not require an interpreter for executing its code. It just requires an internet browser to execute code written in JavaScript.

8. Programming Paradigms Support

Both Python and JavaScript support multi-paradigm programming approaches.

This means that they provide programming support for more than one programming approach. Both languages provide functional, object-oriented, and imperative approaches for programming.

Python also supports procedural programming approach. JavaScript, on the contrary, doesn’t support procedural programming.

9. Modules and libraries

Python comes with several modules for programmers. It's often called a “batteries-included programming language” because of this. As discussed earlier, it includes a wide list of built-in libraries for performing data science, data analytics, and machine learning tasks.

JavaScript offers very few and limited modules. The data, math and JSON modules are examles of this. Additional functionality of JavaScript could be achieved through a host environment (like a web browser).

10. Hash Tables

Python provides built-in hash tables called dictionaries or sets. JavaScript does not offer support of hash tables, although JavaScript objects are a nice substitute.

11. Numeric Data Types

Python allows developers to use multiple numeric data types such as int, float, and decimal point.

JavaScript only allows to use floating numeric datatype.

Final Thoughts

In this article, I discussed the major factors that play into the Python vs. JavaScript debate.

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Written on June 23rd, 2020