2.2Why JavaScript/TypeScript for QA

Aspect	JavaScript	TypeScript
Test frameworks	Jest, Mocha, Playwright Test, Cypress	Same, with type checking
Browser automation	Selenium, Playwright, Cypress, Puppeteer	Same, with autocompletion
API testing	axios, fetch, supertest	Same, with typed responses
Where it dominates	Frontend testing, E2E testing, full-stack apps	Same, with better maintainability
Learning curve	Lower	Slightly higher (types)

TypeScript Advantage for QA

TypeScript catches errors at compile time that would otherwise become flaky tests at runtime:

// Without TypeScript: this bug is found at runtime (maybe)
const userName = response.data.user.nme;  // typo: should be "name"

// With TypeScript: this bug is found immediately in your editor
interface User {
    id: number;
    name: string;
    email: string;
}
const user: User = response.data;
const userName = user.nme;  // TypeScript error: Property 'nme' does not exist