AngularJS is to web-apps what HTML is to dynamic websites. HTML is perfect for stating static documents, but it struggles declaring dynamic views in web-apps. AngularJS extends HTML vocabulary to build expressive, readable, and quick to develop web applications
Rather than abstracting away HTML, CSS, and/or JavaScript or by offering an imperious way to manipulate DOM, AngularJS overcomes HTML competence with dynamic views in a rich web application (RWA).
AngularJS is the frontend part of the MEAN stack, which is also consist of MongoDB database, Express.js web application server framework, Angular.js itself, and Node.js server runtime environment. MEAN stack is the long-term replacement to LAMP stack (Linux, Apache, MySQL, and PHP).
A JavaScript-based opensource, frontend web application framework primarily maintained by Google, AngularJS addresses many challenges to develop single page applications.
Single Page Applications (SPA)
A single-page application (SPA) is very much similar to a web application running on a web browser, except the former interacts with the user by dynamically rewriting the single page rather than loading an entire new page from a server. This approach retains the core user experience between successive pages, making an SPA looks like a mobile application sandboxed inside a web browser.
In an SPA, all the HTML, JavaScript, and CSS elements are retrieved with a single page load. Communication with the single page application repeatedly comprises dynamic communication with the server behind the curtain.
AngularJS framework acclimates and outspreads traditional HTML to present dynamic content through bidirectional data-binding that enables automatic synchronization of models and views. Consequently, AngularJS depreciates plain DOM manipulation with the objective of improving testability and presentation.
Bidirectional data-binding
Data-binding is a programmed way of updating the view every time the model changes, on top of updating the model every time the view changes. That is, any change made in view will mirror in the model and vice a versa. The HTML template is, still, gathered in a web browser. The compilation step generates pure HTML, which the web browser re-renders to reflect on the view. The step is repeated for ensuing page views.
Unlike conventional server-side HTML programming wherein controller and model cooperate inside a server process to create fresh HTML views, AngularJS controller and model states are upheld within the client’s web browser. Consequently, created pages are capable of being created without the need of interacting with the server.
Rich Internet Applications (RIA)
The frontend development of rich internet applications is complicated with vanilla HTML and JavaScript owing to maintainability problems. The plain blend of HTML and JavaScript offers no likelihood to modularize and test the frontend in a clean manner.
AngularJS is an extension of HTML and adds dynamics to static HTML to enable development of maintainable rich internet applications by isolating static UI description and dynamic control logic as per the Model-View-Controller paradigm.
Model View Controller (MVC)
The Model View Controller segregates user interfaces into 3 parts: The model, which contains the data. The view, to which the data is presented to. The controller, which acts as a negotiator between user and model.
To permit communication among model, view and controller, AngularJS relies on Scopes. Scopes are Namespaces that are applied as plain JavaScript objects. An AngularJS app can have one root scope object and, evidently, many child scopes.
Model–View–ViewModel (MVVM)
Models talk to ViewModel objects via a root scope or child scope, which polls the Models for any changes, which is rendered by the Views, which is the HTML that displays your code. Views can be routed using the routeProvider object.
Evidently, AngularJS deep-links and organizes your Views and Controllers, turning them into navigable URLs and provides stateless controllers, which adjust and control the Scope object.
Read more: Develop a web app using MEAN stack
REST Easy
RESTful actions are quickly becoming the standard for communicating from the server to the client. In one line of JavaScript, you can quickly talk to the server and get the data you need to interact with your web pages.
AngularJS turns this into a simple JavaScript object, as Models, following the MVVM (Model View View-Model) pattern.
Dependency Injection (DI)
A developer just passes the dependency to the module and AngularJS takes care of everything and will inject them whenever the application needs.
To produce a controller, pass scope object and other dependencies to the module’s controller function. For instance, to produce a ProductController, we are passing scope object and Calculator service dependencies.
In AngularJS, dependencies can be passed in the following 3 ways. They are as follows:
- Function Arguments
- Array Arguments
- Inject service
Read more: Perfect Business mobile app Framework
Extends HTML
If you look behind the scene (Press Ctrl + U on your browser window), today’s websites are endless streams of < div > tags with little semantic lucidity. As a developer, you have to create extensive and comprehensive CSS classes to define each DOM object. Angular operates HTML like XML, which gives web application developers endless possibilities for tags and attributes.
Angular achieves this, through its HTML compiler and the use of directives to prompt actions based on the newly-created syntax. In a nutshell, Angular Directives are features which boosts the functionality of html elements by integrating new functionalities to them.
Expressions are like code snippets bounded within curly braces, which don’t employ conditional statements or loops. They only format data to display.
Enterprise-level Testing
Aforementioned, AngularJS need no supplementary frameworks or plugins. That goes for testing too. If you're accustomed with projects: QUnit or Jasmine, then you'll have no anxiety learning Angular's unit-testing API and Scenario Runner, which directs you through performing quality analysis as close to the definite state of your production application as possible.
Google Engineers
Angular is built and maintained by dedicated (and brilliant) Google engineers. This means, you not only have a huge open-source community to learn from, but you also have accomplished, shrewd engineers tasked to get your Angular questions answered.
Rising Popularity
According to JavaScript analytics service Libscore, AngularJS is used on the websites of Wolfram Alpha, NBC, Walgreens, Intel, Sprint, ABC News, and about 12,000 other sites out of 1 million tested in October 2016. AngularJS is currently in the top 100 of the most starred projects on GitHub.
Source: Google Trends
Source: Stack Overflow Trends
Popular Websites
The Guardian, Netflix, PayPal, Lego, Upwork, and The Weather Channel websites are built using AngularJS. Google shocked everybody when it announced that it has developed mobile app for Sony PlayStation using AngularJS.
The future of AngularJS
AngularJS has introduced substantial changes from v1.0 to v1.3 to improve every aspect of AngularJS. Post v1.3, in place of looking at developments, the team is on AngularJS 2.0. The confidence is this that from the time the AngularJS has launched, a majority of browsers will be compatible with it so that developers can center their focus on application development. Essentially, the future of AngularJS will be inspiring for all the developers.
