JavaScript is one of the most used program languages today, helping programmers create dynamic and interactive web applications. As developers, we are constantly learning new things to enhance our skill set. If you recently became a JavaScript developer like myself or maybe you’re a seasoned pro looking to dive into something new but not too complex and are wondering what language to dive into next, let me suggest TypeScript- a language that is in high demand today!

Why TypeScript?

As a new developer, it can be overwhelming to know what to dive into next. If you have learned and mastered JavaScript you should consider learning Typescript. Why? Let me explain. Typescript is a superset of javascript, meaning typescript is a language built on top of JavaScript. Even though JavaScript is a very popular and highly demanding skill set, Today, many companies are slowly starting to use TypeScript for front-end development. With this being said Let’s explore the similarities and differences between the two programming languages.

JavaScript vs TypeScript:

Similarities

Since TypeScript is a superset of JavaScript, this means everything you learned in Javascript can be found in Typescript. This means the core syntax and structure are the same, it supports Object-Oriented Programming (OOP) features, asynchronous programming, and more. Because of this, most JavaScript code is also valid TypeScript code, making the transition easy.

Differences

The differences between JavaScript and TypeScript seem small but they’re impactful. Let's start by mentioning the main difference. TypeScript is very similar to JavaScript. One main difference between Javascript and TypeScript is that JavaScript is a dynamic language and Typescript is a static language. In case you don’t remember, I will break down what this means and refresh our terminology.

What is a dynamic language?

A dynamic language is a language where any variable can be assigned any value. This makes it easier to reassign values as needed, resulting in code that's both more adaptable and concise.

What is a static language?

Static languages are programming languages that require variables to be defined with a specific type. This means that once a variable type is assigned, it cannot be reassigned. There is less flexibility.

With this reminder, let's now dive deeper on how these changes look like compared to javascript...

Type Annotations and Type Interface:

Since TypeScript is a static language, variables, functions parameters, and returns, all need to be defined by their types, which are, strings, numbers, arrays, etc. and they cannot be reassigned. TypeScript expects the variable values to match this is also known as type interference.

Let's take a look at this code:

let name: string = "Star";  
let age: number = 25; 

This is type annotation: Specifically adding a type to the variable

Now let's look at this one:

interface Person {
  name: string;
  age: number;
}

const person: Person = {
  name: "Star",
  age: 25,
};

This is type interface: This defines the structure (shape) for an object or class

Both of these provide better control over your code and help prevent mistakes, particularly in large projects, by enhancing type safety.

Handling Errors:

Since you have to specify the type of variable, function parameters, returns, and more, you will be able to detect exactly where the error is. Catching errors is an easier task because of this.

Here's an example:

let age: number = 25;
age = "hello"; // Error: Type 'string' is not assignable to type 'number'

If we attempt to reassign a variable, it will result in an error. This is due to type safety, which ensures that only values of the correct type can be assigned.

Compilation

Unlike JavaScript where code is executed directly to the browser. TypeScript needs to be compiled into JavaScript before it can run. This helps catch errors before the code is executed.

Tips for Learning TypeScript as a JavaScript Developer

1. Start with What You Know: Utilize your existing knowledge of JavaScript and build from there. Begin with the basics and focus on understanding TypeScript’s type system and use of type annotations! Resources like Codecademy and FreeCodeCamp can help guide you through the process.

2. Build on Projects: Start adding TypeScript to small projects, or even recreate existing ones. This is a great way to apply what you're learning practically.

3. Consistency is Key: Practice is everything. Challenge yourself by creating new projects or tackling coding problems on platforms like LeetCode using TypeScript. The more you practice, the better you'll get!

Conclusion

Your knowledge of JavaScript will help you ease into your TypeScript learning. TypeScript will expand opportunities for you as a developer by offering powerful tools, type safety, and clearer code. While JavaScript remains a foundational language, mastering TypeScript can elevate your development skills, making your projects more scalable and maintainable. By embracing TypeScript, you'll not only improve your coding workflow but also position yourself as a more versatile developer in an ever-evolving tech landscape.