The Ember.js components use the W3C web component specification and provide correct encapsulation UI widgets. It contains the three main specifications as templates, shadow DOM, and custom elements.

The components are declared within the data-template-name have a pathname instead of a plain string.

In Ember.js, components specify reusable, composable UI elements that encapsulate both markup and behavior. They allow developers to create custom HTML elements with associated JavaScript functionality, providing a modular approach to building user interfaces. Components encapsulate their own state, making them self-contained and independent, which promotes reusability and maintainability in large applications. Components can accept input data through attributes (known as arguments in Ember.js) and emit actions to communicate changes or trigger behavior. Overall, Ember.js components serve as building blocks for creating complex user interfaces with a clear separation of concerns.