Angular Guide: Component Selectors, Content Projection, and Host Bindings Explained

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Angular supports three types of component selectors — element, attribute, and class — each serving different use cases in the DOM. Attribute selectors allow developers to enhance existing HTML elements, such as a native button, without adding extra DOM nodes, preserving accessibility and styling semantics. The ng-content directive enables content projection, letting parent components pass markup into named or default slots within a child component's template. Multiple projection slots can be defined using the select attribute with standard CSS selectors, and unmatched content falls into a default slot. Style encapsulation in Angular defaults to emulated scoping but can be set to None or ShadowDom depending on how the component interacts with the DOM.

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