The following are the key building blocks of Vue:

• Components: like other SPA frameworks, Vue enables you to decompose your app's visual tree into smaller reusable units called components.
• Data binding: having the view and code separated can be a nuisance as these usually need to interact, and, for that purpose, enter data binding.
• Directives: directives allow us to extend or customize existing elements in all sorts of ways.
• Filters: like Angular's pipes, filters enable us to transform values in an encapsulated and reusable way.
• Plugins: plugins and mixins enable you to extend and customize both global or component-specific options, states, or behavior.
• Reactivity: Vue uses a reactive API to determine and act when changes take place. You can leverage this via data, watches, and computed properties, and even use the underlying API directly.
• Virtual DOM: like React, Vue also implements the concept of virtual DOM. It is essentially a JavaScript object that reflects the actual DOM and takes part of the change detection sequence to optimize updates made to the actual HTML DOM.
• Vue CLI: a command-line interface tool provided to assist you with starting and managing your project.

As you can see, Vue brings with it many features, some of them comparable to Angular and some to React. Despite that, Vue alone is still a slim and lightweight framework, and programmer should learn and start to use it fairly quickly.