If you’ve ever worked on a website development project, you’ve undoubtedly come across JavaScript. Indeed, it has long been the most popular scripting language.
TypeScript is a programming language more suitable for large applications and open-source. Microsoft developed it in 2012, mainly because the JavaScript code became too complex to manage when it came to large-scale applications.
TypeScript is a superset of JavaScript, so generally, anything coded in JavaScript is also valid in TypeScript.
In summary, JavaScript + more features = TypeScript.
So if you save your JavaScript (.js) file with a TypeScript (.ts) extension, it will work fine. However, beware of hasty conclusions. Indeed, TypeScript and JavaScript are different.
Before exposing the differences between the two, let’s understand what each language looks like!
JavaScript
Often abbreviated as JS, JavaScript is a software design language that follows the ECMAScript layout. The compilation of JavaScript is done immediately before execution.
It contains dynamic typing, brace syntax, first-class functions, and prototype-based object orientation. Along with CSS and HTML, JavaScript is one of the core technologies of the web.
JavaScript enables the creation of interactive web pages, an indispensable aspect of modern websites. Since the vast majority of websites use it for the behavior of their client-side pages, it makes sense that all web browsers have a dedicated JavaScript engine for this purpose.
If JavaScript engines were once only present in web browsers, they are now inserted into specific servers (generally via Node.js ). There are many derivatives of JavaScript, like TypeScript, CoffeeScript, Dart, and Kotlin.
These are also implemented in multiple applications trained with frameworks such as Cordova and Electron.
As a multi-paradigm programming language, JavaScript supports the imperative, event, and functional styles and has an application programming interface (API) that allows it to process dates, text, standard data structures, and the Document Object Model ( DOM) without forgetting the regular expressions.
Advantages of JavaScript
JavaScript is the perfect solution for small web projects and teams. It’s common to use JavaScript without the help of build tools, and if you resort to using frameworks, some don’t support TypeScript.
Additionally, using existing JavaScript libraries and frameworks allows you to develop web applications faster while streamlining your software development process.
TypeScript needs to install the JS libraries you want to use: a different type definition results in an extra npm package. So it’s better to use a popular JavaScript library for your development because it will be well-maintained in the future.
TypeScript
TypeScript is an object-oriented and open-source programming language. Created and maintained by Microsoft, TypeScript is a syntactic superset of JavaScript, adding optional static typing along the way.
TypeScript is intended for building large applications and trans-compiles to JavaScript.
Standard JavaScript programs are also valid TypeScript programs, and the language can be used to create JavaScript applications for server-side execution and not just client-side execution.
There are many alternatives for cross-compilation to transform TypeScript into JavaScript; one can use the default TypeScript verifier or the Babel compiler.
TypeScript supports files that can include type data from current JavaScript libraries, just as C++ header files can define the construction of current object files, allowing other programs to exercise the values defined in files as if they were statically typed TypeScript entities.
There are third-party header files for prevalent libraries like D3.js, jQuery, and MongoDB. TypeScript headers for basic Node.js modules are also accessible, allowing the development of Node.js programs in TypeScript.
The TypeScript compiler is written in TypeScript and assembled in JavaScript. It is registered under the Apache 2.0 license.
Advantages of TypeScript
TypeScript is ideal for your large projects, or if your team has many developers working on a large project, then TypeScript is a better option than JavaScript. TypeScript’s access modifiers and the interface can be an added advantage in API communication.
If your project uses React and your team needs to become more familiar with its API, TypeScript offers type definitions. You can also use IntelliSense, which will help you navigate and check out new interfaces.
It takes work to develop simple JavaScript code, especially if you prefer compile-time error checking. With TypeScript, it’s possible to perform run-time type confirmation and validation at compile time.
What are the differences between TypeScript and JavaScript?
Ecosystem
The TypeScript ecosystem is intuitive and powerful, allowing you to statically type various idiomatic JavaScript traits like intersection, union types, and discriminated unions.
JavaScript offers the possibility of discovering and coding without a construction phase.
Data binding
TypeScript uses concepts such as interfaces and types to define the data used. No notion of this type is presented in JavaScript.
Learning curve
TypeScript has a reasonably steep learning curve and requires advanced scripting knowledge.
On the other hand, JavaScript is easy to learn and a flexible language for writing scripts.
Npm packages
With TypeScript, numerous npm packages have static type definitions (or have an external, easier-to-install one).
JavaScript can find and form code, again, without any construction steps.
Annotation and typing
To make the most of these features, TypeScript developers must constantly annotate code, whereas no annotation is needed for JavaScript.
Compiler
The TypeScript code must be compiled, while obviously, there is no obligation to compile the code in JavaScript.
Client-side/server side
Although it can be used on the server side, TypeScript is mostly used on the client side.
JavaScript is used both on the server side and on the client side.
Community
TypeScript has a smaller community of developers than JavaScript, the latter being far more popular with software developers.
Conclusion
Observing the differences between TypeScript and JavaScript, both technologies, while being close, have their advantages and disadvantages.
Indeed, JavaScript may not be the most comprehensive coding language, but it is used alongside HTML to improve the quality of web pages. Moreover, thousands of experienced developers code in JavaScript and are adopted by all browsers.
TypeScript, on the other hand, is an option that remains preferred by developers who want to produce clean and beautiful code that is compact and readable.
Not to mention the various benefits of TypeScript when it comes to live error checking and static typing. The big weak point of TypeScript is that it is not yet native to all web browsers like JavaScript.
Therefore, the conclusion will resume what we had already learned at the beginning of the article: JavaScript is the most suitable when you have a modest team that works on small Web projects. On the other hand, if you have a team with more experience and good knowledge and want to entrust them with managing a more complex project, then TypeScript is a better choice.
TypeScript, even presented as “Super JavaScript,” is not intended to replace or obsolete JavaScript: JavaScript resists and remains the most popular client-side scripting language. Also, for smaller projects, using TypeScript can be an overhead, as translating code into JavaScript takes time, which is an extra step for rendering. Since JavaScript is executed directly on the browser, it is easier to refresh or debug the code for small scripts.
In contrast, in the case of TypeScript, the developer will need an appropriate IDE and configuration to run their code.