Difference Between Angular and AngularJs Decoded!

For most of the front end developers, Angular is a well known framework for web application development. If you want to use Angular in a project, you need to choose one of the versions of Angular.

Angular js was released in 2009 and quickly became popular due its two way data binding, MVC architecture and code reusability. When its contemporary languages like React and Vue started delivering the same advantages as AngularJs with better performance, the Angular team decided to rewrite the framework.

As a result, the team released Angular 2 in 2016. It provided superior performance and improved drawbacks of the original version.

You might have now understood the origin and basics of the Angular framework. Let’s start with Angularjs vs Angular comparison now!

Controllers vs Components

What’s the basic difference in Angular vs AngularJs? Angular is based on TypeScript and AngularJs is based on JavaScript. TypeScript is a superset of ES6 and also backwards compatible with ES5. Angular also possesses the benefits of ES6 such as lambda operators, iterators or reflection’s mechanism.

AngularJs makes use of terms of scope and controller. To scope a variable you can add multiple variables that will be visible in View as well as Controller. It also has a concept of rootScope. Variables in rootScope are available throughout the application.

Instead of using scope or controllers, Angular uses a hierarchy of components as its main architectural concept.

MVC vs Component Architecture

AngularJs is based on the Model View Controller software design pattern. The controllers are defined with $scope variables representing an underlying data model. The data model can be updated in both the view and controller. The view is an HTML file that both displays and updates $scope variables.

Angular 2+ uses more of a component based architecture. Isolated pieces of functionality are defined in the components. These components refer their own templates and stylesheets and are present in a hierarchy of other components.

Dependency Injection

Both Angular and AngularJs use dependency injection. It enables you to share commonly used functionality across different controllers or components.

In AngularJs the dependencies are injected in controller functions, directive definitions and link functions whereas in Angular, constructor functions, declarations and providers are used to manage these dependencies.

Angular CLI

All the versions after Angular 2 feature the Angular CLI - a command line interface to quickly generate the Angular components, services, directives etc. The CLI comes with a convenient set of commands to build your Angular project. It also makes developing your project for different environments easier and allows things such as linting, type checking etc.

On the contrary, AngularJs does not have its own CLI.

Popularity

Before React and Vue came into existence, AngularJs was very popular because it provided an elegant solution to JavaScript SPA with two way data binding and MVC architecture.

Just because it was able to dynamically update a JavaScript POJO from an HTML template created quite a stir in the industry. Due to this, the alternative languages like React and Vue came up with superior diffing algorithms which left AngularJs in the dust.

The Angular framework decided to fight back with the release of Angular 2. Today, it is one of the most popular frameworks for UI development.

Although AngularJs is still used, its popularity has decreased because of other options like Angular 2+, React and Vue.

Performance

Angular is way more faster than AngularJs. Actually it can be said that Angular is 5 times more faster but it depends on the design of your application.

As mentioned above, performance is one of the biggest problems with the original AngularJs. It is due to the factors which made AngularJs so popular. To achieve two way data binding, it relies on a digest cycle for keeping the views in sync with their underlying data models.

AngularJs functions by augmenting all the event handlers with a process called “dirty checking” and each of the scoped variables are compared to their previous values.

If something is changed, the templates and watchers are updated with new values and the process is run again to check if anything else has changed. In this manner, the view is continuously in sync with the data model.

Problem with AngularJs digest cycle is that it is unpredictable. As the applications grow, checking process becomes more intensive and can infinitely run with the two way data flow.

To take care of these issues, Angular team rewrote the framework keeping in mind the flux architecture. Unidirectional data flow was essential to reengineer change detection in Angular.

Advantages of Angular over AngularJs

Some advantages of Angular over AngularJs are listed below:

Performance

Angular is upto 5 times faster than version 1.0 of Angular i.e AngularJs. It is because of a superior diffing algorithm which features unidirectional data flow and component based architecture.

Server Side Rendering

Angular provides extensions to render your application server side. It is an advantage in terms of SEO as certain web crawlers won’t always scrape async content.

Mobile Development

As a framework, Angular makes it possible to develop applications that will work both on browsers and native devices like iOS and Android .

Lazy Loading

It will allow you to asynchronously load JavaScript components based on route. Lazy loading will offer additional performance advantage as the code is only imported while being used.

Tooling

Tooling system provided by TypeScript and NodeJs ecosystem cannot be underestimated. Using Angular CLI, you can generate Angular components, directives, services etc faster without manually copying a bunch of boilerplate code.

Moreover, you can easily build and deploy your project using CLI.

What is Better - Angular or AngularJs?

With the advantages in terms of performance, Angular development seems like the best choice to move forward with. There is a potential learning curve in understanding the NodeJs/TypeScript ecosystem.

One of the few advantages of AngularJs is that it runs in the browser. Using AngularJs for a small application will make sense if you are not willing to learn NodeJs and TypeScript in detail.

Many existing projects are currently using AngularJs and migrating to a newer version may not justify the cost incurred in learning and rewriting the code.