Angular is an open source front-end framework, maintained by Google, used to build rich web applications, especially single-page applications (SPAs) where the interface updates without reloading the page. It is written in TypeScript.
Angular is a complete rewrite of AngularJS, its JavaScript predecessor, which is no longer maintained. The two are incompatible: migrating from one to the other almost amounts to rewriting the application.
Its distinctive feature is being "batteries included": components, routing, forms, HTTP calls, dependency injection and testing tools are provided and structured by the framework. Where React leaves many choices open, Angular imposes an organization. That explains its strong presence in large corporations, banking, insurance and internal business applications, where code consistency across big teams matters more than freedom.
Why it matters when hiring
An Angular developer is not an interchangeable React developer: the core concepts transfer, but the tooling and conventions differ. Check which version the candidate has used, since experience that is mostly AngularJS is dated. In an interview, a good signal is comfort with RxJS, state management and the architecture of a large application in modules or standalone components.