Understanding TypeScript and its file extension

TypeScript is a language that brings new features to JavaScript, while remaining completely compatible with existing JavaScript code. It's useful for when you want to create larger projects, where the codebase might be too complex to manage with just JavaScript.

The answer to the question - "Which of the following filenames is the extension for typescript?" is .ts

The unique file extension associated with TypeScript is .ts. This specific extension is required when you’re writing code in TypeScript. When you see a file with the .ts extension, you can immediately identify it as a TypeScript file.

Let's consider a practical application to understand this better:

Suppose you're working on a large-scale web application and have a TypeScript file named app.ts. This TypeScript file will hold your type-annotated code. Here's a basic example:

// app.ts
let isComplete: boolean = false;
let total: number = 0;
let name: string = 'TypeScript';

In this case, app.ts is a TypeScript file (indicated by the .ts extension) that contains type-annotated code.

By writing code in TypeScript and saving the file with the .ts extension, developers gain numerous benefits, such as static typing, conditional typing, read-only properties, and more. All these features make TypeScript a robust option for coding complex applications.

It's important to note, however, that the web browser cannot directly interpret TypeScript. Hence, the TypeScript code needs to be transcompiled into JavaScript using the TypeScript compiler.

In summary, the .ts extension is distinctively used for TypeScript files. It is a vital part of developing with TypeScript, as it allows the TypeScript compiler to recognize and convert the TypeScript code into JavaScript.