What is TypeScript and why use it

Short answer

TypeScript is a strongly typed superset of JavaScript that compiles to plain JavaScript. It adds optional static typing, interfaces, generics, and advanced tooling to catch errors early.

How it works

TypeScript code is written in .ts files and processed by the TypeScript compiler (tsc) which performs type checking and emits JavaScript. The type system is erased at runtime, meaning compiled output has no type information and runs anywhere JavaScript runs. Editors like VS Code use the TypeScript language service to provide autocomplete, refactoring, and inline error reporting.

Example

function greet(name: string): string {
  return `Hello, ${name}`;
}
console.log(greet('World'));

Why it matters

Static types reduce runtime bugs, improve code readability, and make refactoring safer. In large teams, TypeScript serves as living documentation and enables confident changes across shared modules.