React Hooks (useState, useEffect, useContext) Next.js (SSR, SSG, API Routes) Redux (State Management, Middleware) Zod (Validation) Components (Functional, Class-based) Props (Typechecking with PropTypes) Context API (State Management) React Router (Navigation) Jest (Testing) Styled Components (CSS in JS)

ES6+ (Arrow Functions, Async/Await, Destructuring) DOM Manipulation Fetch API/Axios (HTTP Requests) Webpack (Module Bundling) Babel (JS Transpiler) Lodash (Utility Library) Jest (Testing) Promises and Async Programming Event Handling TypeScript (Static Typing)

Semantic Elements (header, section, article) Forms and Input Types Canvas and SVG for Graphics Video and Audio APIs Local Storage Accessibility (ARIA roles) Responsive Images (srcset) Geolocation API Drag and Drop API Web Workers

Flexbox Grid Custom Properties (Variables) Media Queries (Responsive Design) Transitions and Animations Pseudo-elements (::before, ::after) Pseudo-classes (:hover, :focus) SASS/LESS (Preprocessors) BEM Methodology (Naming convention) CSS Modules (Scoped CSS)