The most popular JavaScript frame­works and libraries

JavaScript (or JS for short) is a scripting language used to make HTML content in­ter­ac­tive in the web browser. This language can be used for both object-ori­en­tat­ed pro­gram­ming as well as pro­ce­dur­al and func­tion­al pro­gram­ming. JavaScript contains pre­de­fined objects (i.e. data elements with special prop­er­ties, methods, or functions) for accessing a web page, but they are sometimes cum­ber­some to use. To help users in writing JS, collected in­for­ma­tion has been made public. These in­struc­tions and tools come in the form of various JavaScript libraries and frame­works, with the aim to make pro­gram­ming easier. We will go through the best and most well-known tools below.

It’s important to keep the two terms separate. Often 'library' and 'frame­work' are used as synonyms even though this is wrong, strictly speaking. Even though the tran­si­tion is seamless in many ways, there are basic dif­fer­ences between the two of them.

A JavaScript library is a library of pre-written JavaScript that enables an easier de­vel­op­ment of JavaScript-based ap­pli­ca­tions. Libraries always ac­com­mo­date sub­pro­grams which, along with support functions, help with the pro­gram­ming process. In contrast to a framework, a library is more developed to one par­tic­u­lar use, meaning it has functions that are co­or­di­nat­ed to each other. For example, the JavaScript library D3.js is used for data vi­su­al­iza­tion – with this library you can implement small tables, diagrams, and sta­tis­tics, as well as more complex graphs (including an­i­ma­tions and in­ter­ac­tions). Libraries are always in­te­grat­ed by a software program: the program accesses the cor­re­spond­ing functions of a program library when they need a specific function. As a result, libraries can only work within a program and can’t run in­de­pen­dent­ly.

A framework is also not an au­tonomous program, but rather a special form of class library. A framework provides the software ar­chi­tec­ture (i.e. the basic structure) of an ap­pli­ca­tion and es­sen­tial­ly de­ter­mines the de­vel­op­ment process. Frame­works have certain design patterns with different functions (often in the form of many libraries) and are used to develop new, in­de­pen­dent ap­pli­ca­tions. An example is the Zend framework for PHP, which is used in Magento’s online store software and web analytics tool Piwik.

Another dif­fer­ence between a framework and a library is how they are managed. With libraries, the code is accessed by pro­gram­mers through a software program’s pro­gram­ming interface. Frame­works, however, carry out an inversion of control: The code is embedded in fixed struc­tures and called up when needed. To summarize, you can say that libraries are called up by programs, whereas frame­works make spec­i­fi­ca­tions to the program.

The core of JavaScript is a rather simple pro­gram­ming language that lends itself par­tic­u­lar­ly well for use within a browser. Many pro­gram­mers face problems with their website interface, or DOM (Document Object Model). Here JavaScript frame­works and libraries come into play, making work a little bit easier for de­vel­op­ers, re­gard­less of their pro­gram­ming field. The JavaScript ex­ten­sions in­tro­duced in the next section can all be down­loaded for free.

JavaScript libraries are reusable codes through which certain features and functions for a website are assigned. jQuery is the most well-known JavaScript library and offers many useful features, although other libraries can be just as helpful.

jQuery

The very extensive jQuery library is the most-used JavaScript library. This is due to the fact that you can write simple cross-browser jQuery code, with lots of plugins available for use. jQuery’s open source library is part of many content man­age­ment systems like WordPress, Drupal, or Joomla!. jQuery also functions as an interface for DOM, offering some of the following functions: CSS3 selectors make it easy to select and ma­nip­u­late website elements. jQuery is also par­tic­u­lar­ly valued for its ability to integrate Ajax requests (HTTP requests without reloading the website).

jQuery UI

jQuery UI is a free extension for jQuery. Its purpose is to define and implement a user interface (UI) from sources like websites or web apps. The focus here is on simple design and in­ter­ac­tions. The functions jQuery has to offer include the pos­si­bil­i­ty to implement in­ter­ac­tive elements (e.g. drag and drop, zooming in and out), an­i­ma­tions, effects, and widgets (like au­to­com­plete, sliders, date picker, etc.). The graphic editor, The­meRoller, can be used to create original themes, or existing themes can be used to adapt for your own purposes. True to its simple design con­fig­u­ra­tion, the modular structure of The­meRoller allows only the necessary com­po­nents to be im­ple­ment­ed.

Dojo Toolkit

The Dojo Toolkit is good for im­ple­men­tat­ing web ap­pli­ca­tions and dynamic web content. As one of the oldest JavaScript libraries that is still relevant on the market, it offers a wide range of functions – the most important com­po­nents of the toolkit are the main program (Dojo), and Dijit, a toolkit for graphical user in­ter­faces. In addition, you can use pre-defined widgets to integrate elements into the website you are creating. Dojo can also handle both DOM and Ajax.

There are con­sid­er­ably more JavaScript libraries than frame­works. The latter are es­pe­cial­ly suitable for complex web ap­pli­ca­tions. If de­vel­op­ers embrace the concepts and spec­i­fi­ca­tions of re­spec­tive frame­works, they will be able to work very ef­fi­cient­ly with them.

AngularJS

This Google-main­tained framework has by far the largest community among the JavaScript frame­works. AngularJS is used (like its main com­peti­tor: Facebook’s library, React) to create single page web ap­pli­ca­tions (web apps, which consist only of HTML documents). Due to the MVVM concept (model-view-viewmodel) of this framework, web ap­pli­ca­tions can be developed that are highly adaptable to user in­ter­ac­tion. (The man­u­fac­tur­ers of the JS framework, however, prefer to cat­e­go­rize AngularJS as MVW: model-view-whatever). Here AngularJS renders the web ap­pli­ca­tion on the client side. The framework is based on jQuery Lite – a slimmed-down version of the well-known JavaScript library, jQuery.

Ember.js

Ember.js is also a client-side framework that is used for im­ple­ment­ing single page web ap­pli­ca­tions, with which you can also create desktop ap­pli­ca­tions. A further dis­tin­guish­ing feature is that the creators of Ember.js in­ten­sive­ly involve the community in the framework’s de­vel­op­ment process; for instance, dis­cussing sig­nif­i­cant framework changes with them before they are im­ple­ment­ed. Ember.js is marketed as a framework for creating ambitious web ap­pli­ca­tions – so it is primarily aimed at de­vel­op­ers who already have ex­pe­ri­ence with designing web ap­pli­ca­tions.

Vue.js

Vue.js is also a JavaScript framework for de­vel­op­ing single-page web ap­pli­ca­tions rem­i­nis­cent of Angular and React. The de­vel­op­ers of this rel­a­tive­ly young and ambitious project de­lib­er­ate­ly designed Vue.js in such a way that beginners find it rel­a­tive­ly easy to get started. For example, it’s possible to integrate templates into HTML. In addition, Vue.js is also said to be much more flexible than many other frame­works, which usually strictly dictate the way the framework is handled.

Frame­works and libraries can con­sid­er­ably smooth the JavaScript pro­gram­ming process. Those mentioned above are only a small portion of the tools that are available. Ad­di­tion­al resources for JavaScript frame­works, libraries, and plugins include GitHub and JavaScript­ing. Here you can find suitable JavaScript ex­ten­sions for various purposes.