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Everything is a component

As an early adopter of Angular and while talking to other people about it, I got frequently asked what the biggest difference is to the first version. My answer to this question was always the same. Everything is a component:

Within the Angular architecture, a component is a directive with an additional view

For me, this paradigm shift was the most relevant change that both simplified and enriched the framework. Of course, there are a lot of other changes with Angular. However, as an advocate of component-based user interfaces, I've found that this change is the most interesting one. Of course, this change also came with a lot of architectural changes.

Angular supports the idea of looking at the user interface holistically and fosters composition with components. However, the biggest difference to its first version is that now, your pages are no longer global views; they are simply components that are assembled from other components. If you've been following this chapter, you'll notice that this is exactly what a holistic approach to user interfaces demands. No more pages, but systems of components.

Angular still uses the concept of directives, although directives are now really what the name suggests. They are orders for the browser to attach a given behavior to an element. Components are a special kind of directive that come with a view.