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<!DOCTYPE html>
<html lang="en" dir="ltr">
<head>
<meta charset="utf-8">
<title>WEB1- JavaScript</title>
</head>
<body>
<h1><a href="index.html">WEB</a></h1>
<input type="button" value="night" onclick = "
var target = document.querySelector('body');
if(this.value=== 'night') {
target.style.backgroundColor = 'black';
target.style.color = 'white';
this.value = 'day'
} else {
target.style.backgroundColor = 'white';
target.style.color = 'black';
this.value = 'night'
}">
<ol>
<li><a href="html.html">HTML</a></li>
<li><a href="css.html">CSS</a></li>
<li><a href="javascript.html">JavaScript</a></li>
</ol>
<h2>JavaScript</h2>
<p>
JavaScript (/ˈdʒɑːvəˌskrɪpt/),[10] often abbreviated JS, is a
programming language that is one of the core technologies of the
World Wide Web, alongside HTML and CSS.[11] Over 97% of websites
use JavaScript on the client side for web page behavior,[12] often
incorporating third-party libraries.[13] All major web browsers have
a dedicated JavaScript engine to execute the code on users' devices.
JavaScript is a high-level, often just-in-time compiled language that conforms
to the ECMAScript standard.[14] It has dynamic typing, prototype-based
object-orientation, and first-class functions. It is multi-paradigm,
supporting event-driven, functional, and imperative programming styles.
It has application programming interfaces (APIs) for working with text,
dates, regular expressions, standard data structures, and the Document
Object Model (DOM).
</p>
</body>
</html>
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