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Best JavaScript Frameworks for developer in 2015

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JavaScript is a lightweight, interpreted programming language with object-oriented capabilities that allows you to build interactivity into otherwise static HTML pages. 
 
JavaScript is: 
<ul>
<li>JavaScript is a lightweight, interpreted programming language</li>
<li>Designed for creating network-centric applications</li>
<li>Complementary to and integrated with Java</li>
<li>Complementary to and integrated with HTML</li>
<li>Open and cross-platform</li>
</ul>
 
JavaScript Frameworks have become a primary element for web design. Almost all websites use JavaScript or Ajax at present, for designing as well as developing purpose. This is probably one of the main elements to improve Web 2.0 style, of designing. 
 
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There are many Java script libraries that have popular reach among the computer users and occupy a special position in the Java script arena. For those who are on a look out for the best, alternative script and solution, the following Java script libraries would be helpful. 
 
Before you may stick on to a particular Java script frame work that may best suit your needs, you will have to analyze on the available Java script libraries. 
 
JavaScript Frameworks are : 
<ol>
<li><a href="http://www.jquery.com/">jQuery</a></li>
<li><a href="http://www.prototypejs.org/">Prototype</a></li>
<li><a href="http://www.mootools.net/">Moo Tools</a></li>
<li><a href="http://www.javascriptmvc.com/">JavaScriptMVC</a></li>
<li><a href="http://developer.yahoo.com/yui/">Developer. Yahoo</a></li>
<li><a href="http://www.qooxdoo.org/">Qooxdo</a></li>
<li><a href="http://mochi.github.com/mochikit/">MochKit</a></li>
<li><a href="http://rialto.improve-technologies.com/wiki/">Rialto</a></li>
<li><a href="http://www.sproutcore.com/">Sproutcore</a></li>
</ol>
 
Hope this article useful for you. Are you favorite Frameworks not in the list? Feel free to mention it in comments below.</div>

Best JavaScript Frameworks for developer in 2015

JavaScript is a lightweight, interpreted programming language with object-oriented capabilities that allows you to build interactivity into...

Top JavaScript Interview Questions and Answers

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<h3 style="text-align: left;">
Top Most frequently Asked JavaScript Interview Questions and Answers for freshers and experienced are below:</h3>
 
1. What is JavaScript? 
-->  JavaScript is a platform-independent,event-driven, interpreted client-side scripting and programming language developed by Netscape Communications Corp. and Sun Microsystems. 
 
2. How is JavaScript different from Java? 
-->  JavaScript was developed by Brendan Eich of Netscape; Java was developed at Sun Microsystems. While the two languages share some common syntax, they were developed independently of each other and for different audiences. 
-->  Java is a full-fledged programming language tailored for network computing; it includes hundreds of its own objects, including objects for creating user interfaces that appear in Java applets (in Web browsers) or standalone Java applications. In contrast, JavaScript relies on whatever environment it's operating in for the user interface, such as a Web document's form elements. 
-->  JavaScript was initially called LiveScript at Netscape while it was under development. A licensing deal between Netscape and Sun at the last minute let Netscape plug the "Java" name into the name of its scripting language. Programmers use entirely different tools for Java and JavaScript. It is also not uncommon for a programmer of one language to be ignorant of the other. The two languages don't rely on each other and are intended for different purposes. 
-->  In some ways, the "Java" name on JavaScript has confused the world's understanding of the differences between the two. On the other hand, JavaScript is much easier to learn than Java and can offer a gentle introduction for newcomers who want to graduate to Java and the kinds of applications you can develop with it. 
 
3. What’s relationship between JavaScript and ECMAScript? 
-->  ECMAScript is yet another name for JavaScript (other names include LiveScript). The current JavaScript that you see supported in browsers is ECMAScript revision 3. 
 
4. How do you submit a form using Javascript? 
-->  Use document.forms[0].submit(); 
(0 refers to the index of the form – if you have more than one form in a page, then the first one has the index 0, second has index 1 and so on). 
 
5. How do we get JavaScript onto a web page? 
-->  You can use several different methods of placing javascript in you pages. 
 
You can directly add a script element inside the body of page. 
1. For example, to add the "last updated line" to your pages, In your page text, add the following: 
blah, blah, blah, blah, blah. 
<script type="text/javascript" > 
 
</script> 
yada, yada, yada. 
(Note: the first comment, "<--" hides the content of the script from browsers that don't understand javascript. The "// -->" finishes the comment. The "//" tells javascript that this is a comment so javascript doesn't try to interpret the "-->". If your audience has much older browsers, you should put this comments inside your javascript. If most of your audience has newer browsers, the comments can be omitted. For brevity, in most examples here the comments are not shown. ) 
The above code will look like this on Javascript enabled browsers, 
 
2. Javascript can be placed inside the <head> element 
Functions and global variables typically reside inside the <head> element. 
<head> 
<title>Default Test Page</title> 
<script language="JavaScript" type="text/javascript"> 
var myVar = ""; 
function timer(){setTimeout('restart()',10);} 
document.onload=timer(); 
</script> 
</head> 
Javascript can be referenced from a separate file 
Javascript may also a placed in a separate file on the server and referenced from an HTML page. (Don't use the shorthand ending "<script ... />). These are typically placed in the <head> element. 
<script type="text/javascript" SRC="myStuff.js"></script> 
 
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6. How to read and write a file using javascript? 
-->  I/O operations like reading or writing a file is not possible with client-side javascript. However , this can be done by coding a Java applet that reads files for the script. 
 
7. How to detect the operating system on the client machine? 
-->  In order to detect the operating system on the client machine, the navigator.appVersion 
string (property) should be used. 
 
8. How can JavaScript make a Web site easier to use? That is, are there certain JavaScript techniques that make it easier for people to use a Web site? 
-->  JavaScript's greatest potential gift to a Web site is that scripts can make the page more immediately interactive, that is, interactive without having to submit every little thing to the server for a server program to re-render the page and send it back to the client. For example, consider a top-level navigation panel that has, say, six primary image map links into subsections of the Web site. With only a little bit of scripting, each map area can be instructed to pop up a more detailed list of links to the contents within a subsection whenever the user rolls the cursor atop a map area. With the help of that popup list of links, the user with a scriptable browser can bypass one intermediate menu page. The user without a scriptable browser (or who has disabled JavaScript) will have to drill down through a more traditional and time-consuming path to the desired content. 
 
9. How can JavaScript be used to improve the "look and feel" of a Web site? By the same token, how can JavaScript be used to improve the user interface? 
-->  On their own, Web pages tend to be lifeless and flat unless you add animated images or more bandwidth-intensive content such as Java applets or other content requiring plug-ins to operate (ShockWave and Flash, for example). 
-->  Embedding JavaScript into an HTML page can bring the page to life in any number of ways. Perhaps the most visible features built into pages recently with the help of JavaScript are the so-called image rollovers: roll the cursor atop a graphic image and its appearance changes to a highlighted version as a feedback mechanism to let you know precisely what you're about to click on. But there are less visible yet more powerful enhancements to pages that JavaScript offers. 
-->  Interactive forms validation is an extremely useful application of JavaScript. While a user is entering data into form fields, scripts can examine the validity of the data--did the user type any letters into a phone number field?, for instance. Without scripting, the user has to submit the form and let a server program (CGI) check the field entry and then report back to the user. This is usually done in a batch mode (the entire form at once), and the extra transactions take a lot of time and server processing power. Interactive validation scripts can check each form field immediately after the user has entered the data, while the information is fresh in the mind. 
-->  Another helpful example is embedding small data collections into a document that scripts can look up without having to do all the server programming for database access. For instance, a small company could put its entire employee directory on a page that has its own search facility built into the script. You can cram a lot of text data into scripts no larger than an average image file, so it's not like the user has to wait forever for the data to be downloaded. 
-->  Other examples abound, such as interactive tree-structure tables of contents. More modern scriptable browsers can be scripted to pre-cache images during the page's initial download to make them appear lickety-split when needed for image swapping. I've even written some multi-screen interactive applications that run entirely on the client, and never talk to the server once everything is downloaded. 
 
10. What are JavaScript types? 
-->  Number, String, Boolean, Function, Object, Null, Undefined. 
 
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11. How do you convert numbers between different bases in JavaScript? 
-->  Use the parseInt() function, that takes a string as the first parameter, and the base as a second parameter. So to convert hexadecimal 3F to decimal, use parseInt ("3F", 16); 
 
12. How to create arrays in JavaScript? 
-->  We can declare an array like this 
var scripts = new Array(); 
We can add elements to this array like this 
scripts[0] = "PHP"; 
scripts[1] = "ASP"; 
scripts[2] = "JavaScript"; 
scripts[3] = "HTML"; 
 
Now our array scrips has 4 elements inside it and we can print or access them by using their index number. Note that index number starts from 0. To get the third element of the array we have to use the index number 2 . Here is the way to get the third element of an array. 
document.write(scripts[2]); 
We also can create an array like this 
var no_array = new Array(21, 22, 23, 24, 25); 
 
13. How do you target a specific frame from a hyperlink? 
-->  Include the name of the frame in the target attribute of the hyperlink. <a href=”mypage.htm” target=”myframe”>>My Page</a> 
 
14. What is a fixed-width table and its advantages? 
-->  Fixed width tables are rendered by the browser based on the widths of the columns in the first row, resulting in a faster display in case of large tables. Use the CSS style table-layout:fixed to specify a fixed width table. 
If the table is not specified to be of fixed width, the browser has to wait till all data is downloaded and then infer the best width for each of the columns. This process can be very slow for large tables. 
Example of using Regular Expressions for syntax checking in JavaScript 
... 
var re = new RegExp("^(&[A-Za-z_0-9]{1,}=[A-Za-z_0-9]{1,})*$"); 
var text = myWidget.value; 
var OK = re.test(text); 
if( ! OK ) { 
alert("The extra parameters need some work.\r\n Should be something like: \"&a=1&c=4\""); 
} 
 
15. Where are cookies actually stored on the hard disk? 
-->  This depends on the user's browser and OS. 
In the case of Netscape with Windows OS,all the cookies are stored in a single file called 
cookies.txt 
c:\Program Files\Netscape\Users\username\cookies.txt 
In the case of IE,each cookie is stored in a separate file namely username@website.txt. 
c:\Windows\Cookies\username@Website.txt 
 
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16. How to add Buttons in JavaScript? 
-->  The most basic and ancient use of buttons are the "submit" and "clear", which appear slightly before the Pleistocene period. Notice when the "GO!" button is pressed it submits itself to itself and appends the name in the URL. 
<form action="" name="buttonsGalore" method="get"> 
Your Name: <input type="text" name="mytext" /> 
 
<input type="submit" value="GO!" /> 
<input type="reset" value="Clear All" /> 
</form> 
Another useful approach is to set the "type" to "button" and use the "onclick" event. 
<script type="text/javascript"> 
function displayHero(button) { 
alert("Your hero is \""+button.value+"\"."); 
} 
</script> 
<form action="" name="buttonsGalore" method="get"> 
<fieldset style="margin: 1em; text-align: center;"> 
<legend>Select a Hero</legend> 
<input type="button" value="Agamemnon" onclick="displayHero(this)" /> 
<input type="button" value="Achilles" onclick="displayHero(this)" /> 
<input type="button" value="Hector" onclick="displayHero(this)" /> 
<div style="height: 1em;" /> 
</fieldset> 
</form> 
 
17. What can javascript programs do? 
-->  Generation of HTML pages on-the-fly without accessing the Web server. The user can be given control over the browser like User input validation Simple computations can be performed on the client's machine The user's browser, OS, screen size, etc. can be detected Date and Time Handling 
 
18. How to set a HTML document's background color? 
-->  document.bgcolor property can be set to any appropriate color. 
 
19. How can JavaScript be used to personalize or tailor a Web site to fit individual users? 
-->  JavaScript allows a Web page to perform "if-then" kinds of decisions based on browser version, operating system, user input, and, in more recent browsers, details about the screen size in which the browser is running. While a server CGI program can make some of those same kinds of decisions, not everyone has access to or the expertise to create CGI programs. 
-->  For example, an experienced CGI programmer can examine information about the browser whenever a request for a page is made; thus a server so equipped might serve up one page for Navigator users and a different page for Internet Explorer users. 
-->  Beyond browser and operating system version, a CGI program can't know more about the environment. But a JavaScript-enhanced page can instruct the browser to render only certain content based on the browser, operating system, and even the screen size. 
-->  Scripting can even go further if the page author desires. For example, the author may include a preference screen that lets the user determine the desired background and text color combination. A script can save this information on the client in a well-regulated local file called a cookie. The next time the user comes to the site, scripts in its pages look to the cookie info and render the page in the color combination selected previously. The server is none the wiser, nor does it have to store any visitor-specific information. 
 
20. Are you concerned that older browsers don't support JavaScript and thus exclude a set of Web users? individual users? 
-->  Fragmentation of the installed base of browsers will only get worse. By definition, it can never improve unless absolutely everyone on the planet threw away their old browsers and upgraded to the latest gee-whiz versions. But even then, there are plenty of discrepancies between the scriptability of the latest Netscape Navigator and Microsoft Internet Explorer. 
-->  The situation makes scripting a challenge, especially for newcomers who may not be aware of the limitations of earlier browsers. A lot of effort in my books and ancillary material goes toward helping scripters know what features work in which browsers and how to either workaround limitations in earlier browsers or raise the compatibility common denominator. 
-->  Designing scripts for a Web site requires making some hard decisions about if, when, and how to implement the advantages scripting offers a page to your audience. For public Web sites, I recommend using scripting in an additive way: let sufficient content stand on its own, but let scriptable browser users receive an enhanced experience, preferably with the same HTML document.</div>

Top JavaScript Interview Questions and Answers

Also Read: Android Interview Ques & Ans for Fresher Top Most frequently Asked JavaScript Interview Questions and Answers for ...

What is JavaScript? And Resources to Learn it

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What is JavaScript? 
 JavaScript is a programming language which is used to create web pages more interactive. It runs on your visitor's PC or laptop and doesn't need regular download from your site. It is frequently used to generate polls and quizzes. JavaScript is the Netscape-developed object scripting language used in millions of web pages and server applications worldwide. • It can function as both a procedural and an object oriented language • It can interrelate with HTML source code, enabling Web authors to jazz up their websites with dynamic content. • It is endorsed by a number of <a href="http://www.cbil360.com/" style="color: #888888; text-decoration: none;" target="_blank">web design companies</a> ( or software companies) and is an open language that anybody can use without purchasing a license. 
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 JavaScript Online Resources to learn it ->>>  JavaScript Guide : https://developer.mozilla.org/en-US/docs/JavaScript/Guide JavaScript Tutorial: http://www.w3schools.com/js/default.asp JavaScript - Wikipedia, the free encyclopedia: http://en.wikipedia.org/wiki/JavaScript JavaScript Kit- Your comprehensive JavaScript: http://www.javascriptkit.com/ The JavaScript Source: http://www.javascriptsource.com/ Hello World of JavaScript The Hello World example is usually normal to take in when talking about programming languages. So here we go /* 
<blockquote style="background-color: white; color: #666666; font-family: 'Trebuchet MS', Trebuchet, Verdana, sans-serif; font-size: 13px; line-height: 18px;">
Hello, World! You can also pop alert boxes just as easily with:</blockquote>
*/  
 
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 Yes, i.e, all you need. You don’t need to include any file or import any packages. Everything to facilitate is needed to execute JavaScript is provided by the web browser (or the client) so it is also known as Client Side Scripting Language. So Finally JavaScript is broadly supported. It is accessible in the following browsers:  • Netscape Navigator (beginning with version 2.0)  • Microsoft Internet Explorer (beginning with version 3.0)  • Firefox  • Safari  • Opera  • Google Chrome  • Any other browser whose vendor licensed or implemented JavaScript. Therefore, the majority Internet users today have web browsers that support JavaScript. That's why JavaScript is one of the most accepted tools in the Web developer's arsenal.

What is JavaScript? And Resources to Learn it

What is JavaScript? JavaScript is a programming language which is used to create web pages more interactive. It runs on your visitor...