TypeScript vs. JavaScript

TypeScript vs. JavaScript ”; Previous Next TypeScript and JavaScript are the most popular programming languages widely used in web development. If you are a web developer, you must have heard about them. Do you know the difference between JavaScript and TypeScript, or have you ever been confused about choosing between them? If yes, we have covered the difference between them, which one you should choose between them, and how to migrate from JavaScript to TypeScript. JavaScript Initially, in 1994, JavaScript was developed for the Netscape browser to add interactivity to web pages. After that, in 1997, the first standardized version of JavaScript was launched. In the starting phase, JavaScript was used to add interactivity to the web pages. For example, to add a click event, form submission event, etc. So, it was used with HTML and CSS and became a fundamental scripting language for them. Nowadays, JavaScript is also used for backend development. For example, NodeJS is used to create the backend of the web applications. In simple terms, JavaScript is a cross-platform programming language, which can be used to develop the frontend and backend of the application. Features of JavaScript Here are some basic features of JavaScript. Dynamic Typing − JavaScript variables don’t have fixed types. So, it provides the flexibility in assigning the values to the variables. First-Class Functions − In JavaScript, functions can be expressions. So, it can be assigned to a variable, passed as arguments, and returned from other functions. Prototypal Inheritance − JavaScript supports prototype-based inheritance, which can be achieved by modifying the object prototypes. However, it also supports class-based inheritance. Asynchronous Programming − JavaScript supports asynchronous programming with callbacks, promises, and async/await. Cross-platform support − JavaScript is supported by all modern web browsers and other platforms. It is also used to develop the front end and backend of web applications. So, it is a platform-independent programming language. Example In the code below, the add() function takes two numbers as an argument. In the function body, we sum the values of the parameters ‘a’ and ‘b’ and use the ‘return’ keyword to return the summation of both parameters. // JavaScript example: Adding two numbers function add(a, b) { return a + b; } console.log(add(5, 10)); // Output: 15 The output of the above example code is as follows – 15 TypeScript TypeScript is very similar to JavaScript, and it has almost the same syntax as JavaScript. In 2012, Microsoft created TypeScript as an open-source project to solve the issues faced by developers while using JavaScript. So, TypeScript contains all the features that JavaScript has and contains some extra features to solve additional issues of typing. TypeScript has static typing which is more useful in large projects in which multiple developers are working together. Whenever you compile the TypeScript code, it compiles the code in JavaScript, and then you can use NodeJS to run the compiled TypeScript code. Features of TypeScript Here are some features of TypeScript, which are not available in JavaScript. Static Typing − TypeScript allows you to specify types for each variable, function parameter, and return value. This feature helps in catching errors at compile time. Interfaces − TypeScript is an object-oriented programming language, and it contains the interfaces to define the structure of objects that help in improving code readability and maintainability. Classes and Inheritance − TypeScript supports classes and classical inheritance, making it easier to create complex structures. Compatibility − TypeScript is compatible with all versions of JavaScript. JavaScript Features − TypeScript is a superset of JavaScript. So, you can use all JavaScript features, methods, libraries, etc. in TypeScript. Example In the code below, we have defined the ‘number’ type for the function parameters, which was not there in the JavaScript code. However, both code produces the same output. // TypeScript example: Adding two numbers function add(a: number, b: number): number { return a + b; } console.log(add(5, 10)); // Output: 15 On compiling, it will generate the following JavaScript code. // TypeScript example: Adding two numbers function add(a, b) { return a + b; } console.log(add(5, 10)); // Output: 15 The output of the above example code is as follows – 15 Key Differences Between JavaScript and TypeScript The main difference between TypeScript and JavaScript is typing, as JavaScript has dynamic typing and TypeScript has static typing. However, we have covered some more differences between them in the table below. Feature JavaScript TypeScript Typing Dynamic typing Static typing Compilation Interpreted by browsers/Node.js Compiled into JavaScript Error Detection Runtime errors Compile-time errors Tooling Support Basic Advanced (autocompletion, refactoring, etc.) Prototypal Inheritance Uses prototypes Supports classes and classical inheritance Use Cases Small to medium projects, quick prototyping Large projects, complex applications Code Maintainability Can be harder in large codebases Easier due to static typing and interfaces Interfaces Not natively supported Supported, and improved code structure Type Inference Not available Available, reduces the need for explicit types Access Modifiers Not supported Supports private, public, and protected modifiers Asynchronous Programming Callbacks, Promises, async/await Same as JavaScript, with type safety When to Use JavaScript? JavaScript can be used in various situations, and here are some of them. Smaller Projects − If you want to create smaller projects like static company or personal portfolio, you may use JavaScript. Quick Prototyping − If you want to create a quick prototype of the application, you can use JavaScript instead of TypeScript. However, you can migrate JavaScript to TypeScript later. Learning Curve − JavaScript is easier for beginners to pick up due to its simpler syntax and lack of strict typing requirements. When to Use TypeScript? TypeScript is well-suited for various situations: Large Projects − When you are creating large or real-time projects, you should use TypeScript. In large projects, multiple developers work together. So, TypeScript makes it easier for them to know variable type, return type of function values, etc. Code Maintainability − Makes maintaining and refactoring code easier with static typing and interfaces. Error Detection − Allows for catching errors at compile-time rather

TypeScript – Home

TypeScript Tutorial PDF Version Quick Guide Resources Job Search Discussion TypeScript Tutorial TypeScript lets you write JavaScript the way you really want to. TypeScript is a typed superset of JavaScript that compiles to plain JavaScript. TypeScript is pure object oriented with classes, interfaces and statically typed like C# or Java. The popular JavaScript framework Angular 2.0 is written in TypeScript. Mastering TypeScript can help programmers to write object-oriented programs and have them compiled to JavaScript, both on server side and client side. This TypeScript tutorial has been designed for beginners as well as working professional to help them understand the basic to advance concepts of TypeScript. It covers most of the important concepts related to TypeScript such as type system, control flow, functions, interfaces, classes and objects, advanced types, type manipulation, generics, namespace, modules, decorators and many more. Why to Learn TypeScript? TypeScript is a popular choice for developing web applications. It is also used in other areas such as game development and server-side development. TypeScript is a free and open-source high-level programming language. It’s very easy to learn if you are already familiar with JavaScript. You need to understand the type system and related syntax to apply them to JavaScript code. By mastering TypeScript, you”ll be well-positioned for a variety of software development roles. In addition to the above, here are some more reasons to learn the TypeScript programming language: It adds static typing with optional type annotations to JavaScript. TypeScript is designed for the development of large applications. It helps developers catch errors early in their code editor. It supports all the latest ECMAScript features. TypeScript is the recommended language for creating apps with the Angular framework. It can also be used for game development and server-side development. All the big companies such as Microsoft, Google, Meta, Amazon, etc., use TypeScript. TypeScript supports JavaScript libraries. You can easily use JavaScript libraries in your TypeScript projects. A huge community of TypeScript is available on the internet and growing rapidly. Anyone can easily get support. There are tons of jobs available for those who know TypeScript. Applications of TypeScript TypeScript is a versatile programming language that can be applied across a wide range of applications. Web development: TypeScript is extensively used in building dynamic and interactive web applications. The popular framework Angular is entirely built on TypeScript, and other JavaScript frameworks such as React and Vue.js support TypeScript. TypeScript enables developers to create robust web applications with enhanced type safety and better tooling support. Server-side development: TypeScript is increasingly used with server-side development with Node.js. Frameworks like NestJS use TypeScript to build server-side applications. Mobile development: With TypeScript, you can develop cross-platform mobile applications using frameworks like React Native. Desktop app development: TypeScript can also be used to develop desktop applications through frameworks like Electron. Game development: TypeScript is used in game development, particularly for web-based games. Large-scale development: TypeScript is well suited for large-scale applications. Its static typing, interfaces, and modularization capabilities help keep the codebase organized and scalable. Library and framework development: You can develop your own library or framework using TypeScript. Many popular frameworks are written in TypeScript. Who Should Learn TypeScript? Programmers coming from the Object-Oriented world will find it easy to use TypeScript. With the knowledge of TypeScript, they can build web applications much faster, as TypeScript has good tooling support. Prerequisites to Learn TypeScript As a reader of this tutorial, you should have a good understanding of OOP concepts and basic JavaScript to make the most of this tutorial. TypeScript Jobs The demand for TypeScript developers has been steadily increasing as more companies adopt it for their projects. Here are some of the most popular companies that offer the role of TypeScript developer: Microsoft Google Meta Amazon Netflix Airbnb Many more… TypeScript Career Opportunities There are several career paths that you can choose after learning TypeScript. Here, we have listed some of them: Web developer Front-end developer Back-end developer Full-stack developer Game developer Mobile developer DevOps Engineer Many other roles Libraries and Frameworks Many popular frameworks and libraries are either entirely written in TypeScript or support TypeScript. Some of the popular frameworks/libraries are as follows: Angular: It is developed entirely with TypeScript. React: It supports TypeScript through DefinitelyTyped type definitions and official support. Vue.js: It provides TypeScript support via the Vue CLI. NestJS: It is a progressive Node.js framework built with TypeScript for building efficient and scalable server-side applications. Compile/Execute TypeScript Programs We have provided Typescript Online Compiler which helps you to Edit and Execute the code directly from your browser. Try to click the icon to run the following Typescript code to print conventional “Hello, World!”. Try to change the value of string variable and run it again to verify the result. var message:string = “Hello World” console.log(message) On compiling, it will generate following JavaScript code. var message = “Hello World”; console.log(message); Frequently Asked Questions About TypeScript There are some very Frequently Asked Questions(FAQ) about TypeScript, this section tries to answer them briefly. What is Typescript, and how does it differ from JavaScript? TypeScript is an open-source programming language that is an extended version of JavaScript. It is statically typed and built on top of the existing syntax and functionalities in JavaScript. Typescript can be integrated easily with the JavaScript eco-system and modern frameworks like React and Angular, making it reliable for creating and managing large-scale web-applications. Typescript”s advanced features include classes, interfaces and generics which facilitate the design of modular code for complex web applications. The typed annotations and extended OOP features aid in understanding, debugging and maintaining code. Additionally, Typescript executes strict null checks, unlike JavaScript, which helps to identify null or undefined values during compilation, hence reducing the runtime errors. Why should I use TypeScript? TypeScript provides several benefits, including: Type Safety: Helps catch errors early through static type checking. Enhanced Tooling: Offers better code editors” support with features like autocompletion, navigation, and refactoring. Improved Code Quality: Enforces coding standards and best practices. Better Collaboration: Makes