TypeScript and JavaScript: Their relationship, explained

Ellen Weaver
January 17, 2023
5
min read

Are you confused about the relationship between TypeScript and JavaScript? Are you wondering if TypeScript is just a fancier version of JavaScript? Or maybe you're curious about the pros and cons of using TypeScript and when it's best to use it?

In this article, we will dive into the details and explore the similarities and differences between TypeScript and JavaScript. We'll also cover the pros and cons of using TypeScript, and when it's best to use it for different types of projects. By the end of this article, you will have a clear understanding of the relationship between TypeScript and JavaScript, and be able to make an informed decision about which one to use for your next project.

The relationship between JavaScript and TypeScript

TypeScript is a typed superset of JavaScript, meaning that it's a version of JavaScript with additional features. All valid JavaScript code is also valid TypeScript code, so you can use any existing JavaScript libraries in a TypeScript project. However, TypeScript adds a number of features that are not present in JavaScript, such as static typing, class-based object-oriented programming, and interfaces.

TypeScript code needs to be transpiled (compiled) into plain JavaScript before it can be run in a browser or on a server. This process involves the TypeScript compiler analyzing the code and generating equivalent JavaScript code that can be executed. The generated JavaScript code is often more efficient and easier to optimize than the original TypeScript code, as it does not contain the type annotations and other additional syntax. In this way, TypeScript acts as a layer on top of JavaScript, adding additional features and capabilities that can be leveraged when needed, but which are ultimately compiled down to plain JavaScript for execution.

What is JavaScript?

Adobe Stock Image, JavaScript

JavaScript is a programming language that's been around since the mid-90s, and it's still incredibly relevant today. JavaScript is used to make web pages interactive and dynamic, and it's also used on the server-side with technologies like Node.js. JavaScript is widely used across the web, powering many of the interactive and dynamic features of modern websites. It's essentially the language of the web.

Because JavaScript is a high-level programming language, it's easier for humans to understand and write compared to low-level languages like assembly. It's a versatile language that can be used for a wide range of tasks from simple scripts to complex web applications.

JavaScript is a widely used and supported programming language with a large and active developer community. With that, JavaScript has an extensive ecosystem of libraries and tools, many of them open-source and well-documented, which allows developers to perform complex tasks with ease.

However, JavaScript doesn't have the added features and structure of TypeScript, which may make it less suitable for large-scale, complex projects. Additionally, JavaScript's dynamic nature can also make it less secure and more prone to errors if not properly managed.

JavaScript uses

Front-end

JavaScript is a popular language for front-end web development. A popular example of using JavaScript for front-end development is the React library. React is a JavaScript library created and maintained by Facebook, which allows developers to build reusable components and manage the state of a web application. It's widely adopted by many companies and organizations such as Airbnb, Netflix, and Asana.

Back-end

On the other hand, JavaScript can also be used for back-end development. A popular example of using JavaScript for back-end development is Node.js. Node.js is a JavaScript runtime that allows developers to build server-side applications using JavaScript. Node.js is widely used for building scalable and efficient back-end systems, and is also used by many large companies such as Netflix, Uber, and PayPal.

Pros of JavaScript

JavaScript has many benefits that make it a popular choice among developers. One of the main pros of JavaScript is its wide usage and support. JavaScript is one of the most widely-used programming languages in the world, and as a result, has an active and large developer community.  It's uses range from front-end and server-side to mobile app development, automation, and artificial attention. This means that there are a wealth of resources available for learning and using JavaScript, including tutorials, forums, and open-source libraries. Additionally, this active community means that there are always new developments and updates being made to the language, keeping it at the forefront of web development.

Another pro of JavaScript is its dynamic nature. JavaScript is a dynamic language, which means that it allows developers to change the types of variables and properties of objects on the fly. This makes it a highly flexible and easy-to-use language, which can be beneficial for developers working on small to medium-sized projects. It also allows for faster development times as developers can quickly make changes and refactor code without having to worry about rigid type systems. This flexibility makes JavaScript well-suited to agile development methodologies and iterative development cycles. It also provides flexibility when working with data, making it easier to manipulate and handle data from APIs or JSON, reducing the risk of errors.

Pros of JavaScript summarized:

  • Popular and widely used resulting in a wealth of resources and support
  • Wide range of use cases, from front-end web development to server-side programming, mobile app development, automation, and artificial intelligence
  • Faster development times and well-suited to agile development methodologies and iterative development cycles
  • Easily modified
  • Its dynamic nature makes it easy to work with data
  • when working with APIs or JSON, it can make working with it more simple and less prone to errors.

Cons of JavaScript

JavaScript has several cons that should be considered when deciding whether to use it for a project. One of the main cons lies within one of its pros: it's a dynamic language. JavaScript's dynamic nature can make it less secure and more prone to errors if not properly managed. This is because the lack of strict typing can lead to unexpected behavior and data type mismatches. This can be particularly problematic in larger and more complex projects, where keeping track of all the different variables and data types is more difficult. Subsequently, JavaScript's issues with typing was a driving factor in the creation of TypeScript.

Another con of JavaScript is that it lacks some of the added features and structure of TypeScript, like static typing, class-based object-oriented programming, interfaces, namespaces, and decorators, which may make it less suitable for large-scale, complex projects. This can make it harder to maintain organization and readability in the code, which can lead to issues with scalability and extensibility. Additionally, JavaScript's dynamic nature can also make it less suited for high-performance tasks that require more predictable behavior and performance. This is because JavaScript is an interpreted language and its code runs slower than compiled languages.

Cons of JavaScript summarized:

  • Can be less secure and more prone to errors if not properly managed
  • Lack of strict typing can lead to unexpected behavior and data type mismatches
  • Lacks the features and structure of TypeScript, making it less suitable for large-scale, complex projects
  • More difficult to maintain organization and readability in the code
  • Less suited for high-performance tasks that require more predictable behavior and performance
  • It's an interpreted language, meaning code runs slower than compiled languages like C++, C#

What is TypeScript?

Adobe Stock Image, TypeScript

Like mentioned above, TypeScript is a programming language that builds on top of JavaScript by adding optional static typing and other advanced features. It was first developed and released by Microsoft in 2012, and has since grown in popularity among developers. Its creators developed TypeScript to meet the needs of users who faced issues with JavaScript, the most prevalent being JavaScript's shortcoming regarding type systems.

TypeScript includes other advanced features such as interfaces and classes, which allow for more structured and organized object-oriented programming. This can help to make code more readable and reusable, and also allows for better code-sharing and collaboration among teams. TypeScript has a built-in compiler that can catch errors before the code runs, which can save time and effort in debugging. This also means that TypeScript code needs to be transpiled into JavaScript before it can run in a browser or on a server. This extra step can be seen as a pro or a con depending on the development team's perspective. For some developers, the added structure and features of TypeScript are a major benefit, while others may prefer the simplicity and flexibility of JavaScript.

TypeScript uses

Front-end

When it comes to front-end development, TypeScript can be used in combination with popular libraries and frameworks such as Angular, React and Vue. Angular, for example, is a popular platform for building web applications, and is written in TypeScript. Using TypeScript in Angular enables developers to use the powerful features of TypeScript such as static typing and class-based object-oriented programming, making it easier to create complex and scalable web applications. This also helps to maintain better code organization and readability which is important when building large scale projects.

Back-end

On the backend, TypeScript can be used to develop Node.js applications, which allows developers to build scalable network applications using JavaScript. Node.js is a popular choice for building server-side applications, and the use of TypeScript can help to improve the maintainability and scalability of these applications by providing static typing, class-based OOP, and other features that are not available in plain JavaScript. Additionally, TypeScript can also be used for building backends using frameworks like NestJS which help to build scalable and maintainable backend systems.

Pros of TypeScript

One of the main benefits of using TypeScript is that it provides added features and structure to your code, which can help with maintainability and organization. For example, TypeScript's static typing helps to catch errors early during development, which can save a lot of debugging time later on. This feature also makes it easier to reason about the structure of your code and understand how different pieces of the codebase interact with each other.

Another benefit of TypeScript is that it's becoming increasingly popular and well-supported in the development community. As a result, more and more libraries, frameworks, and tools are being developed with TypeScript in mind, making it easier to integrate and use with other tools. This can be a big advantage when working on large-scale projects, where organization and maintainability are key. Additionally, TypeScript provides optional class-based OOP (Object Oriented Programming) and interfaces which allows for more organized and maintainable code, especially for large-scale projects.

Pros of TypeScript summarized:

  • TypeScript provides added features and structure to your code, which can help with maintainability and organization
  • Static typing helps to catch errors early during development, saving debugging time
  • TS makes it easier to reason about the structure of your code and understand how different pieces of the codebase interact with each other
  • TS provides optional class-based OOP and interfaces for more organized and maintainable code
  • TypeScript is becoming increasingly popular and well-supported in the development community
  • More libraries, frameworks, and tools are being developed with TypeScript in mind, making it easier to integrate and use with other tools
  • Supported by popular libraries and frameworks which is an advantage when working on large-scale projects

Cons of TypeScript

One of the main cons of using TypeScript is that it can have a steeper learning curve than JavaScript, especially for developers who are not familiar with the syntax. TypeScript adds a layer of complexity to the development process, and it can take some time to become proficient with the language and its features. Additionally, it requires developers to invest time in understanding the type system, which can slow down the development process.

Another con of TypeScript is that its added features and structure might be considered as overkill for small or simple projects. For such projects, the added benefits of TypeScript may not justify the added complexity and development time. The type-checking and class-based object-oriented programming features of TypeScript are geared towards larger, more complex projects, which can make it less suitable for smaller projects that don't need the added structure and organization.

Another con of TypeScript is that it requires additional setup and configuration compared to plain JavaScript, as the TypeScript code needs to be transpiled into JavaScript before it can run in a browser or on a server. This can add an extra step to the development process and require additional setup and maintenance for the project's build pipeline. If the project's configuration isn't set up correctly, it can lead to issues and errors during the transpilation process.

Cons of TypeScript summarized:

  • TypeScript can have a steeper learning curve than JavaScript
  • TypeScript adds complexity to development process
  • Requires time to become proficient with language and features
  • Type-checking and class-based OOP geared towards large, complex projects
  • May not be suitable for small projects that don't need added structure and organization.
  • Another con of TypeScript is that it can increase the overall build and compilation time, which can slow down the development process and make it less suitable for projects with tight deadlines.

What should you use for your project, JavaScript or TypeScript?

Adobe Stock Images, JavaScript or TypeScript Decision

Ultimately, when deciding between TypeScript and JavaScript, it's important to consider the goals and requirements of your project. The choice may also depend on the team's experience and preference, as well as the availability of libraries and frameworks that support the language.

When deciding to use TypeScript, it's important to consider the size and complexity of the project, the team's experience and preference, and the need for static typing and other additional features that TypeScript provides. Its static typing and class-based object-oriented programming features provide a more structured and organized approach to coding, making it easier to create complex and reusable code. This can be especially useful for projects that have multiple developers working on the same codebase, as it helps to catch errors early on in the development process, saving time and effort in debugging.

For example, imagine you're building an e-commerce application with a team of developers. With TypeScript, you can create interfaces for different types of products, such as "Electronics" and "Clothing," which ensures that every product object adheres to a certain set of properties and methods. This makes the code more readable and less prone to errors, making it easier to work with for the entire team.

JavaScript should be used over TypeScript when the project is small and doesn't require the added features and structure that TypeScript provides, such as static typing and class-based object-oriented programming. Also, if the development team is not familiar with TypeScript and its syntax, it may be easier to stick with JavaScript as it has a more straightforward learning curve. If the project is primarily focused on front-end web development and doesn't have complex and large scale requirements, JavaScript can be more suitable as it has an extensive ecosystem of libraries and tools for this purpose.

Additionally, it's important to consider the long-term maintainability and scalability of your project. With TypeScript’s added features, it offers a more robust type system, improved code organization and readability which makes the code more maintainable and scalable over time. JavaScript on the other hand, being more flexible, could be more prone to errors and might not be as scalable. It's crucial to consider this aspect when choosing the right language for your project.

Conclusion

TypeScript and JavaScript are both powerful programming languages that have their own strengths and weaknesses. TypeScript, being a supercharged version of JavaScript, offers added features such as static typing and class-based object-oriented programming that make it easier to create complex and large-scale projects. JavaScript, on the other hand, is known for its simplicity and flexibility, making it a great choice for small to medium-sized projects.

Both languages have active developer communities and extensive ecosystems of libraries and tools. It ultimately comes down to the specific needs and goals of a project as well as the experience and preference of the development team when deciding which language to use. It is important to consider the size and complexity of the project, and the need for static typing and other additional features that TypeScript provides, before making a decision. With a good understanding of the pros and cons of both languages, developers can make informed decisions and choose the right language for their project.

Share this post