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Vue js

In an industry where frameworks backed by large companies dominate, a framework built by one person is stealing the show. Offering a welcome change from React and Angular, Vue.js aims to make available the most desirable features from both frameworks, and its trademark simplicity means it’s fast becoming the framework of choice.


What is Vue.js?

Vue.js is an open-source front-end JavaScript framework with a reputation for making interactive web development projects fast, friendly and flexible to create. Compared to alternatives like React and Angular, development in Vue.js has a low barrier to entry as skill level goes, but it works for a wide variety of use cases. In some ways it resembles React and Angular, though it differs in some crucial areas. For example, both React and Vue.js use a virtual DOM and a component-based architecture and boast lightweight libraries for their core functionality. And Angular and Vue.js have in common their use of directives and two-way data binding.

While preserving these core features, Vue.js offers complete freedom in how you structure your projects. There’s no need to use JSX or lock yourself into a particular app structure. Its flexibility allows you to use it for entire projects or as a small component in an existing system. Perhaps most importantly, thanks to its two-way data binding and selective re-rendering, Vue.js offers great performance with minimal interference. In many cases, Vue.js apps can be lighter and better optimized than their React and Angular counterparts.

The name Vue.js itself originates in the Old French vue (“view”), serving as both a reference to how Vue.js structures its projects into different “views” and how it places its focus on the view layer of an application.


How does Vue.js work?

Virtual DOM

Like React, Vue.js uses a virtual document object model (DOM) to provide a developer-friendly interface for synchronizing an application’s state with its real DOM. Reading and updating the actual DOM of an HTML web page is painfully slow and resource-intensive. With this in mind, Vue.js relies on keeping a copy of the real DOM in memory and operating on the in-memory copy. Whenever there’s a change to the app’s data, Vue.js updates the state of components that rely on that data. The application is then re-rendered into the virtual DOM and reconciled with the real DOM in the fewest possible direct changes.

Two-way data binding

Vue.js differs from React in how it keeps user inputs consistent with the application’s data model. React requires the developer to handle program state changes manually. In contrast, Vue.js relies on two-way data binding, which makes the process much less complex. Two-way data binding synchronizes the view and the model; whenever data in the model changes, the view updates automatically — no need for setState() methods or hooks. Vue.js handles it all via “watchers” attached to every component instance that automatically detect when state changes occur. And unlike React, Vue.js doesn’t re-render the entire view, but just the components relying on the data that changed.

Components

Vue.js apps are organized into trees of nested reusable components, each of which is a reusable Vue instance that keeps its view and logic independent of other components. A component’s structure specifies the data it returns and how it should be rendered on a page:

// Define a new component called counter
Vue.component('counter', {

  // The data property returns a data object for each unique component instance
  data: function () {
    return {
      count: 0
    }
  },

  // The template property specifies how the component is displayed (in HTML)
  template: '<button v-on:click="count++">Count: {{ count }}</button>'
})

Using components makes Vue.js code reusable, modular and much easier to maintain.

Model-view-viewmodel framework

The core library of Vue.js serves as a bridge between the v**iew and the m**odel of a web app via two-way data binding. Almost serving to replace the controller in an MVC framework, Vue.js behaves as does a v**iew m**odel in MVVM design architecture.

In a full-stack web application, Vue.js’s core library isn’t responsible for holding data. Instead, it listens for data changes as a middleman and communicates them between the view and model. This direct communication between the view and model works fine for single-page applications, but note that you may need a more sophisticated controller and/or Vue.js plugins for multi-page applications. In such a case, companion frameworks like Nuxt.js can extend Vue.js’s influence to include the back end.


Benefits of using Vue.js

Selective re-rendering

Much of Vue.js’s performance benefits stem from its use of selective re-rendering. Unlike React, Vue.js automatically watches each component for any state changes. When it detects a change, it only updates components that rely on that data rather than the entire sub-component tree, significantly increasing an application's scalability. Selective re-rendering ensures performance doesn’t degrade as the component tree and code base increase in size.

By default, React re-renders all sub-components of the newly updated component. While React can mimic selective re-rendering (using shouldComponentUpdate functions), Vue.js handles it out of the box.

HTML templating syntax

Vue.js uses simple HTML templating syntax for building projects. When compiled, these templates bind the DOM to the component instance’s data using virtual-DOM rendering functions. Using directives and JavaScript wrapped in curly brackets, Vue.js builds reactivity into a template like this:

<!-- Renders an item component instance from a Vue.js script -->
<div> {{ item }} </div>

<!-- Renders an image with its source set to image_src via the v-bind directive -->
<img v-bind:src="image_src">

<!-- Changes styling of a button depending on the values of isPrimary and isLight -->
<button v-bind:class="{ 'btn-primary' : isPrimary, 'btn-light': isLight}"></button>

There’s no need to learn JSX, which might represent a sizable adjustment for newer developers or designers. And while JSX is more powerful, HTML templates make a lot of that power accessible with no learning curve. Finally, if you do end up needing JSX for a complex project, Vue.js supports it.

Large ecosystem and rising popularity

Vue.js is still young, but in the time it’s been around it’s amassed a huge ecosystem that caters to a wide variety of use cases. In addition to the core library, it boasts companion libraries that handle everything from routing (Vue Router), state management (Vuex), server-side rendering (vue-server-renderer), and even unit testing (Vue Test Utils). And those are just the libraries built by the Vue.js team; there are plenty more built by and for the community.

Due to Vue.js’s rising popularity, it also has a growing and active community behind it. Its members are constantly discussing and solving problems and building projects. Where the extensive documentation falls short, the community makes up for it with numerous videos, blog posts and forum discussions.


Drawbacks to using Vue.js

Less mature tools for non-browser rendering

For rendering outside the browser, Vue.js partners with Weex, allowing you to use the same simple templating syntax inside the browser and out. However, Weex is still in early development and therefore isn't as proven and reliable as alternatives for other frameworks like React Native. As a result, you won’t find as much support from documentation or the community when building a Weex app with Vue.js. In such cases, React Native might be the better choice.

Much smaller share of the job market

Compared to React and Angular, Vue.js is younger and lacks backing from large companies like Facebook and Google. While it has caught up in popularity, as measured by stars on its GitHub repository, its share of the job market remains small. Currently, React and Angular are at least twice as prevalent as Vue.js in job listings.

So whether you’re looking to hire employees or looking for work, using Vue.js might represent a potential hindrance versus using React or Angular.


What is Vue.js used for?

Web applications

Vue.js powers countless examples of web apps for all kinds of use cases. When used with just its core library, Vue.js is best for single-page web apps. The rest of the Vue.js ecosystem makes it relatively easy to build scalable, multi-page applications. Developers can start and scale production-ready projects using Vue CLI. And, similar to Redux for React, Vuex adds and manages global state management via central stores. For multiple pages, Vue Router can configure routes and navigation in an application. These extensions and many more in the ecosystem offer just about any functionality you might need.

Desktop and mobile applications

In conjunction with Electron, Vue.js allows you to build modern, native desktop and mobile applications. All you need to get started is a simple API to connect the Vue.js and Electron layers. Plenty of libraries like electron-vue-api and electron-vue exist to help simplify the work and flatten the learning curve.

Static site generation

Using Vue.js with the companion framework Nuxt.js, you can build a statically generated or “JAMStack” website that doesn't need a server with its pre-rendered Vue.js pages. The end result is an SEO-optimized, blazing-fast website that’s cheap and easy to deploy.


FAQ

Is Vue.js easier to learn than React?

If you're used to HTML syntax and separating JavaScript and CSS from templates, you’ll find Vue.js much easier to learn than React’s all-inclusive JSX component syntax. Vue.js also takes care of a lot of state-management optimizations by default. React places the responsibility for these optimizations at the developer’s feet.

All in all, Vue.js is less opinionated in how it wants you to work and requires less developer intervention. It's also widely considered to have better documentation.

Is Vue.js faster than React?

Both React and Vue.js adopt the virtual DOM approach for reconciling differences between an application’s model and view. However, as we mentioned above, React requires the developer to manage state-management optimizations. Vue.js, by means of two-way data binding, manages it by default. Further, Vue.js can be much lighter than React for typical applications. This improves start-up times and more efficient memory allocation in your application.

In view of the foregoing, Vue.js can and should be quicker than React. But despite their different approaches, real-world metrics show that the two have similar levels of performance.

For larger, more complex applications, React's manual state handling might be preferable. But projects of all sizes can benefit from Vue.js’s out-of-the-box optimizations.

Who created Vue.js?

Vue.js was created by Evan You, a former AngularJS developer working at Google. The framework was born of his frustration with the heavy, structured approach of Angular. In creating it, Evan sought to take the best parts of both Angular and React and combine them into one easy-to-use, lightweight framework.

Is Vue.js suitable for single-page web apps?

Definitely. Vue.js’s component-based architecture and state-management capabilities make it perfect for building modular, scalable single-page web applications. Adaptability is also one of Vue.js’s strong points. It can integrate into an existing project, but it also offers all the functionality required to start from scratch. Check out this guide on how to build a single-page application using the Vue.js ecosystem and Firebase.


Summary

Vue.js has clearly earned its rising popularity in the developer community. Combining the sought-after benefits of React and Angular in an easy-to-use package brings developers in, and Vue.js’s two-way data binding, HTML templating syntax and selective re-rendering makes them stick around.

Starting with its initial release, Vue.js was made to build a wide variety of project types, from web apps to native desktop and mobile variants and even statically generated sites.

However, it’s not the perfect framework just yet. Given its youth, Vue.js’s share of the job market is still tiny compared to that of React and Angular, so using it may not represent a stepping stone to career progression. And its simplicity may be too limiting for larger, more complex projects that require the structure and customizability of frameworks like React and Angular.

Whether Vue.js is appropriate for your next project boils down to a single question: Do you value simplicity or complexity?