TypeScript vs JavaScript: Understanding the Key Differences 

What should you choose for your business—JavaScript or Typescript? The question seems challenging to answer at first, but when you compare the ins and outs of both programming languages, you can understand which one is BEST or BETTER. 

Though JavaScript has been a decade-old language, it’s still popular amongst most developers who want to create interactive websites and applications. 

But there’s another open-source scripting language available – Typescript which allows developers to create complex-level enterprise web apps. On top of that, it comes with more extra functionalities and features to smoothen your web development process.  

This blog will give you a quick wake-up call regarding the key differences between JavaScript and Typescript and which is a good fit for your web development project. 

What’s Typescript? 

Typescript is a superset of JavaScript, an important programming tool in web development, for creating complex web applications. Superset in this case means that Typescript contains all features and syntax on top of JavaScript. Essentially, it extends the capabilities of JavaScript. 

The people at Microsoft developed and maintained this programming language.  

Typescript is an upgraded version of JavaScript and is suitable for client and server-side applications. It adds static typing, interfaces, and classes to JavaScript. 

Unlike JavaScript, which is dynamically typed, Typescript is a static typing language that allows you to catch errors at the compile time not at the run time.  

Through static typing, developers need to define the type of variable when writing the code which makes it safer to work with. Let’s say you want to define variable X as 14 and if you recall this function with wrong values, then the language would throw an error. 

Cleaner code leads to fewer runtime errors. This makes the code more readable and maintainable, making it a viable option when working on large-scale projects. 

In nutshell, it’s a modern tool for web development as it has more powerful features, easier to code, faster to learn, and quicker to debug. Moreover, it’s highly compatible with various programming frameworks such as React, Angular, and Vue. 

What’s JavaScript?  

JavaScript is a dynamically typed language, that is used for adding interactivity to websites, web apps, servers, or games. You can add dynamic features to web pages that cannot be done by HTML or CSS. It works with HTML and CSS to create dynamic frontends. 

JavaScript was initially used for front-end development needs but now it can be scaled for back-end development projects as well. 

One recent study found that 98.9% of websites use JavaScript as a client-side programming language.  

JavaScript can be suitable for smaller projects or when you need something up or can run quickly. It generally has a smaller learning curve. 

It’s flexible but runs the risk of error as web developers can’t catch it during compile time. They can find unexpected errors during execution time as they can’t define the variable type while writing code. 

If you are to settle between JavaScript or Typescript, it all boils down to your project needs and your preferences. 

Features of Typescript  

Let’s discuss some of the popular features of Typescript-  

1. Static typing  

Unlike JavaScript, Typescript is a statically typed language as the developer needs to define the type of variable at the compile time not during the run time.   

For Instance – name: string  

id: number  

By defining each variable in Typescript, you make the code more readable and maintainable. Supposedly you change the value of variables, and it’s statically typed, then the Typescript compiler will throw an error.  

Here, the compiler adds the verification badge, and it will not pass an incorrect value during the code checking process as shown in the example below. 

2. Compatible with JavaScript versions  

JavaScript remains the backbone of Typescript meaning whatever code you write in JavaScript works well in Typescript. As Typescript is compatible with old and new JavaScript versions, it means that the entire JavaScript code can be compiled and run on any browser.

3. Decorators  

Decorator is one of the newest features in Typescript that enhances your code readability. These are declarations that are added to classes and functions to modify their behavior.  

By adding decorators in Typescript, you enhance the functionality of classes.  

You can add decorators using @expression (@symbol is added before declaration).  

4. Classes and Interfaces  

It acts as the container, structure, or blueprint for the set of behaviors and has several components –  

• Fields  
• Methods  
• Constructors  

While classes are present in JavaScript, Typescript does have a class with some advanced features.  

Alternatively, interface is used in Typescript to define the structure of an object. It’s used for type checking and helps developers to find runtime errors during the development process.   

The interface represents different properties, and the developer can only access property defined under that interface. If the property doesn’t exist or isn’t defined under that interface, then it will throw a type error.  

Example of Input  

Example of output  

Differences between Typescript and JavaScript  

Basis of comparison	Typescript	JavaScript
1. Learning curve	Typescript has a steeper learning curve for beginners who’re new to static typing concepts. It is challenging to learn typescript as you are required to master the JavaScript fundamentals first before moving to Typescript.    However, if you have a good understanding of writing JavaScript code then the learning curve could be moderate for you.  You can learn the ins and outs of Typescript with ease such as complex syntax, interfaces, static typing, generics, class declaration, type definition, etc.	JavaScript has a smaller learning curve as it’s easy to learn this programming language because of its simple syntax and extensive use cases. Its strength lies in simplicity.    To learn JavaScript code, you just need a text editor and web browser to learn the game.
2 .Syntax	Syntax for writing Typescript can be written as –  Var message: string = “HelloWorld” console.log (message)	The syntax for writing JavaScript includes –  // How to create variables:  var x;  let y;    // How to use variables:  x = 5;  y = 6;  let z = x + y;
3. Developers community	Typescript has a smaller but growing community of developers. You can find plenty of tutorials and online resources to solve your typescript-related problem.     Sometimes, you need to apply JavaScript answers in your own Typescript program.	JavaScript has huge community support as it has been there for decades.    Whenever developers feel stuck, they can get help from libraries, frameworks, and plenty of samples to speed up their development work.
4. Compatability	Typescript needs to be compiled into plain JavaScript output.    Once you’ve done it, you can run it everywhere that’s running on the web browser.	JavaScript runs everywhere almost on any web browser.   It’s the default scripting language and you can run it on multiple browsers.
5.Tools and frameworks	Typescript has an integration with the editor, and it can fix errors before they occur at runtime.    Usually, most code editors support Typescript as you just need to provide configuration information on how you may want to use it.	JavaScript has various web development frameworks such as ReactJs, Angular and VueJs.

What are the benefits of choosing Typescript over JavaScript?  

Let’s talk about the good things about choosing Typescript over JavaScript-  

1. Typescript is a static programming language as it calls for errors during the compilation, not during the runtime.  

2. Researcher states that Typescript can catch 15% of all JavaScript errors. It means it’s faster to debug. This saves developers time because they can now focus on resolving logic errors, not the common defects.  

3. Typescript is an extended version of JS with ES6 or ECMA script which includes arrow function and template literals. This allows developers to write clever yet cleaner code (write less and do more).  

4. It’s more suitable for managing large-scale projects with complex codebases. Moreover, it’s a more updated version of JavaScript as it’s packed with additional functionalities.  

Can Typescript replace JavaScript?  

Although Typescript is making WAVES in the web development industry. But it doesn’t mean that the popularity of JavaScript will fade.  

Typescript would never replace JavaScript as it’s a superset of this programming language. It means that all JavaScript code is also valid in Typescript.  

Typescript provides several benefits over JavaScript in terms of optional static typing and other features of JavaScript (interfaces, modules) that help in improving code quality.  

JavaScript always remains the core element as this is the language that browsers understand and execute. As Typescript can’t be implemented for all browsers, the entire code can be converted into JavaScript by changing the file extension and then executed inside the browser.  

Moreover, there is a greater interoperability between JavaScript and TypeScript. It means that all the JavaScript packages are available in Typescript.  

Why should you migrate your project to Typescript?  

Migrating your project from JavaScript to Typescript is important for to following reasons –  

• Code Maintainability  

As Typescript contains a static typing system, it becomes easy to catch the bugs in the early stages of the development process which makes the code more readable and error-free, especially for large-scale projects.  

When incorrect values are assigned to variables or a wrong argument is passed through the function, the compiler raises an error.  

The compiler checks for type-related errors at the compilation time, not during the run time. 

• Makes your project more scalable  

Switching to Typescript is a good option when working with large-scale projects as it follows a structured approach where complexity is concerned. It enhances code readability as it uses reusable components which makes the development process smoother.  

• More tools and a better ecosystem  

Typescript has a good set of tools, libraries, and frameworks such as best-in-class IDEs, Visual Studio code, WebStorm, etc. It is integrated with the JavaScript ecosystem, so developers get the flexibility to use the JavaScript code in their projects. 

Thus, migration from JavaScript to Typescript becomes smoother.  

When should you choose JavaScript or Typescript?  

There are mainly key factors to consider when choosing between JavaScript or Typescript –  

• Choose Typescript when you’re working with large-scale projects. Typescript static typing system helps developers to manage code complexity. That’s why you need to consider the size and complexity of projects. 

If you’re working with small-scale projects that need simple logic, go with JavaScript because it’s a loosely typed language.  

• Migrating to Typescript becomes easy when your development team is proficient in using JavaScript. The choice between JavaScript or Typescript depends on the expertise and skillset of the team, project complexity, and scalability.  

• If you need long-term support and maintenance for your application, then Typescript is the best choice for your business. Its error-checking capabilities make your code more readable and maintainable so there would be less maintenance cost in the long run.  

Wrapping up  

This blog has given you insights on how Typescript is different from JavaScript. Undoubtedly, Typescript is a good fit for projects with complex data structures or when your business is dealing with complex web applications. It’s easy for developers to catch errors and make the code more readable.  

But choose JavaScript when you simply want to add interactivity to websites or applications for projects that aren’t complex. 

Whatever language you use for web development, think about your project size, your business goals, and scalability. 

As a progressive web application development company, we validate your app idea, perform market research, and then create future-ready applications that enhance the user experience and help you reach your target audience.  

Just tell us your business needs and we’ll help you out with that.