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HTML

              
                <script src="https://cdn.freecodecamp.org/testable-projects-fcc/v1/bundle.js"></script>

<!DOCTYPE html>
<html>
<head>

	<script src="https://cdn.freecodecamp.org/testable-projects-fcc/v1/bundle.js">
	</script>
	<link href='https://fonts.googleapis.com/css?family=Aldrich' rel='stylesheet'>
	<link href='https://fonts.googleapis.com/css?family=Asap' rel='stylesheet'>
	<!--meta=mobile friendly-->
	<meta content="width=device-width, initial-scale=1, shrink-to-fit=no" name="viewport">
	<title></title>
</head>
<body>
	<main id="main-doc">
		<h1>JavaScript Documentation</h1>
		<section class="main-section" id="Introduction">
			<header>
				<h3>Introduction</h3>
			</header>
			<article>
				<p>JavaScript is a cross-platform, object-oriented scripting language. It is a small and
				lightweight language. Inside a host environment (for example, a web browser), JavaScript can be
				connected to the objects of its environment to provide programmatic control over them.</p>
				<p>JavaScript contains a standard library of objects, such as Array, Date, and Math, and a core
				set of language elements such as operators, control structures, and statements. Core JavaScript
				can be extended for a variety of purposes by supplementing it with additional objects; for
				example:</p>
				<ul>
					<li>Client-side JavaScript extends the core language by supplying objects to control a browser
					and its Document Object Model (DOM). For example, client-side extensions allow an application
					to place elements on an HTML form and respond to user events such as mouse clicks, form input,
					and page navigation.</li>
					<li>Server-side JavaScript extends the core language by supplying objects relevant to running
					JavaScript on a server. For example, server-side extensions allow an application to
					communicate with a database, provide continuity of information from one invocation to another
					of the application, or perform file manipulations on a server.</li>
				</ul>
			</article>
		</section>
		<section class="main-section" id="What_you_should_already_know">
			<header>
				<h3>What you should already know</h3>
			</header>
			<article>
				<p>This guide assumes you have the following basic background:</p>
				<ul>
					<li>A general understanding of the Internet and the World Wide Web (WWW).</li>
					<li>Good working knowledge of HyperText Markup Language (HTML).</li>
					<li>Some programming experience. If you are new to programming, try one of the tutorials
					linked on the main page about JavaScript.</li>
				</ul>
			</article>
		</section>
		<section class="main-section" id="JavaScript_and_Java">
			<header>
				<h3>JavaScript and Java</h3>
			</header>
			<article>
				<p>JavaScript and Java are similar in some ways but fundamentally different in some others. The
				JavaScript language resembles Java but does not have Java's static typing and strong type
				checking. JavaScript follows most Java expression syntax, naming conventions and basic
				control-flow constructs which was the reason why it was renamed from LiveScript to
				JavaScript.</p>
				<p>In contrast to Java's compile-time system of classes built by declarations, JavaScript
				supports a runtime system based on a small number of data types representing numeric, Boolean,
				and string values. JavaScript has a prototype-based object model instead of the more common
				class-based object model. The prototype-based model provides dynamic inheritance; that is, what
				is inherited can vary for individual objects. JavaScript also supports functions without any
				special declarative requirements. Functions can be properties of objects, executing as loosely
				typed methods.</p>
				<p>JavaScript is a very free-form language compared to Java. You do not have to declare all
				variables, classes, and methods. You do not have to be concerned with whether methods are
				public, private, or protected, and you do not have to implement interfaces. Variables,
				parameters, and function return types are not explicitly typed.</p>
			</article>
		</section>
		<section class="main-section" id="Hello_World">
			<header>
				<h3>Hello World</h3>
			</header>
			<article>
				To get started with writing JavaScript, open the Scratchpad and write your first "Hello world"
				JavaScript code: <code>function greetMe(yourName) { alert("Hello " + yourName); }
				greetMe("World");</code> Select the code in the pad and hit Ctrl+R to watch it unfold in your
				browser!
			</article>
		</section>
		<section class="main-section" id="Variables">
			<header>
				<h3>Variables</h3>
			</header>
			<article>
				<p>You use variables as symbolic names for values in your application. The names of variables,
				called identifiers, conform to certain rules.</p>
				<p>A JavaScript identifier must start with a letter, underscore (_), or dollar sign ($);
				subsequent characters can also be digits (0-9). Because JavaScript is case sensitive, letters
				include the characters "A" through "Z" (uppercase) and the characters "a" through "z"
				(lowercase).</p>
				<p>You can use ISO 8859-1 or Unicode letters such as å and ü in identifiers. You can also use
				the Unicode escape sequences as characters in identifiers. Some examples of legal names are
				Number_hits, temp99, and _name.</p>
			</article>
		</section>
		<section class="main-section" id="Declaring_Variables">
			<header>
				<h3>Declaring Variables</h3>
			</header>
			<article>
				You can declare a variable in three ways:
				<p>With the keyword var. For example, <code>var x = 42.</code> This syntax can be used to
				declare both local and global variables.</p>
				<p>By simply assigning it a value. For example, <code>x = 42.</code> This always declares a
				global variable. It generates a strict JavaScript warning. You shouldn't use this variant.</p>
				<p>With the keyword let. For example, <code>let y = 13.</code> This syntax can be used to
				declare a block scope local variable. See Variable scope below.</p>
			</article>
		</section>
		<section class="main-section" id="Variable_Scope">
			<header>
				<h3>Variable Scope</h3>
			</header>
			<article>
				<p>When you declare a variable outside of any function, it is called a global variable, because
				it is available to any other code in the current document. When you declare a variable within a
				function, it is called a local variable, because it is available only within that function.</p>
				<p>JavaScript before ECMAScript 2015 does not have block statement scope; rather, a variable
				declared within a block is local to the function (or global scope) that the block resides
				within. For example the following code will log 5, because the scope of x is the function (or
				global context) within which x is declared, not the block, which in this case is an if
				statement.</p><code>if (true) { var x = 5; } console.log(x); // 5</code>
				<p>This behavior changes, when using the let declaration introduced in ECMAScript
				2015.</p><code>if (true) { let y = 5; } console.log(y); // ReferenceError: y is not
				defined</code>
			</article>
		</section>
		<section class="main-section" id="Global_Variables">
			<header>
				<h3>Global Variables</h3>
			</header>
			<article>
				<p>Global variables are in fact properties of the global object. In web pages the global object
				is window, so you can set and access global variables using the window.variable syntax.</p>
				<p>Consequently, you can access global variables declared in one window or frame from another
				window or frame by specifying the window or frame name. For example, if a variable called
				phoneNumber is declared in a document, you can refer to this variable from an iframe as
				parent.phoneNumber.</p>
			</article>
		</section>
		<section class="main-section" id="Constants">
			<header>
				<h3>Constants</h3>
			</header>
			<p>You can create a read-only, named constant with the const keyword. The syntax of a constant
			identifier is the same as for a variable identifier: it must start with a letter, underscore or
			dollar sign and can contain alphabetic, numeric, or underscore characters.</p>
			<pre><code>const PI = 3.14;</code></pre>
			<p>A constant cannot change value through assignment or be re-declared while the script is
			running. It has to be initialized to a value.</p>
			<p>The scope rules for constants are the same as those for let block scope variables. If the
			const keyword is omitted, the identifier is assumed to represent a variable.</p>
			<p>You cannot declare a constant with the same name as a function or variable in the same scope.
			For example:</p>
			<pre><code>// THIS WILL CAUSE AN ERROR
function f() {};
const f = 5;
// THIS WILL CAUSE AN ERROR ALSO
function f() {
  const g = 5;
  var g;
  //statements
}</code></pre>
			<p>However, object attributes are not protected, so the following statement is executed without
			problems.</p>
			<pre><code>const MY_OBJECT = {"key": "value"};
MY_OBJECT.key = "otherValue";</code></pre>
		</section>
		<section class="main-section" id="Data_Types">
			<header>
				<h3>Data Types</h3>
			</header>
			<p>The latest ECMAScript standard defines seven data types:</p>
			<ul>
				<li>
					<p>Six data types that are primitives:</p>
					<ul>
						<li>
							<p>Boolean. true and false.</p>
						</li>
						<li>
							<p>null. A special keyword denoting a null value. Because JavaScript is case-sensitive, null
							is not the same as Null, NULL, or any other variant.</p>
						</li>
						<li>
							<p>undefined. A top-level property whose value is undefined.</p>
						</li>
						<li>
							<p>Number. 42 or 3.14159.</p>
						</li>
						<li>
							<p>String. "Howdy"</p>
						</li>
						<li>
							<p>Symbol (new in ECMAScript 2015). A data type whose instances are unique and
							immutable.</p>
						</li>
						<li>
							<p>and Object</p>
						</li>
					</ul>
				</li>
			</ul>
			<p>Although these data types are a relatively small amount, they enable you to perform useful
			functions with your applications. Objects and functions are the other fundamental elements in
			the language. You can think of objects as named containers for values, and functions as
			procedures that your application can perform.</p>
		</section>
		<section class="main-section" id="If...else_Statement">
			<header>
				<h3>If...else Statement</h3>
			</header>
			<p>Use the if statement to execute a statement if a logical condition is true. Use the optional
			else clause to execute a statement if the condition is false. An if statement looks as
			follows:</p>
			<pre><code>if (condition) {
  statement_1;
} else {
  statement_2;
}</code></pre>
			<p>condition can be any expression that evaluates to true or false. See Boolean for an
			explanation of what evaluates to true and false. If condition evaluates to true, statement_1 is
			executed; otherwise, statement_2 is executed. statement_1 and statement_2 can be any statement,
			including further nested if statements.</p>
			<p>You may also compound the statements using else if to have multiple conditions tested in
			sequence, as follows:</p>
			<pre><code>if (condition_1) {
 statement_1;
} else if (condition_2) {
  statement_2;
} else if (condition_n) {
  statement_n;
} else {
  statement_last;
} </code></pre>
			<p>In the case of multiple conditions only the first logical condition which evaluates to true
			will be executed. To execute multiple statements, group them within a block statement<code>({
			... }) .</code>In general, it's good practice to always use block statements, especially when
			nesting if statements:</p>
			<pre id="ifcode"><code>if (condition) {
statement_1_runs_if_condition_is_true;
statement_2_runs_if_condition_is_true;
} else {
statement_3_runs_if_condition_is_false;
statement_4_runs_if_condition_is_false;
}</code></pre>
			<p>It is advisable to not use simple assignments in a conditional expression, because the
			assignment can be confused with equality when glancing over the code. For example, do not use
			the following code:</p>
			<pre><code>if (x = y) {
  /* statements here */
}</code></pre>
			<p>If you need to use an assignment in a conditional expression, a common practice is to put
			additional parentheses around the assignment. For example:</p>
			<pre><code>if ((x = y)) {
  /* statements here */
}</code></pre>
		</section>
		<section class="main-section" id="While_Statement">
			<header>
				<h3>While Statement</h3>
			</header>
			<p>A while statement executes its statements as long as a specified condition evaluates to true.
			A while statement looks as follows:</p>
			<pre><code>while (condition)
      statement</code></pre>
			<p>If the condition becomes false, statement within the loop stops executing and control passes
			to the statement following the loop.</p>
			<p>The condition test occurs before statement in the loop is executed. If the condition returns
			true, statement is executed and the condition is tested again. If the condition returns false,
			execution stops and control is passed to the statement following while.</p>
			<p>To execute multiple statements, use a block statement <code>({ ... })</code> to group those
			statements.</p>
			<p>Example:</p>
			<p>The following while loop iterates as long as n is less than three:</p>
			<pre><code>var n = 0;
var x = 0;
while (n &lt; 3) {
 n++;
 x += n;
}</code></pre>
			<p>With each iteration, the loop increments n and adds that value to x. Therefore, x and n take
			on the following values:</p>
			<ul>
				<li>After the first pass: n = 1 and x = 1</li>
				<li>After the second pass: n = 2 and x = 3</li>
				<li>After the third pass: n = 3 and x = 6</li>
			</ul>
			<p>After completing the third pass, the condition n &lt; 3 is no longer true, so the loop
			terminates.</p>
		</section>
		<section class="main-section" id="Function_Declarations">
			<header>
				<h3>Function Declarations</h3>
			</header>
			<article>
				<p>A function definition (also called a function declaration, or function statement) consists
				of the function keyword, followed by:</p>
				<ul>
					<li>The name of the function.</li>
					<li>A list of arguments to the function, enclosed in parentheses and separated by commas.</li>
					<li>The JavaScript statements that define the function, enclosed in curly brackets, { }.</li>
				</ul>
				<p>For example, the following code defines a simple function named square:</p>
				<pre><code>function square(number) {
 return number * number;
}</code></pre>
				<p>The function square takes one argument, called number. The function consists of one
				statement that says to return the argument of the function (that is, number) multiplied by
				itself. The return statement specifies the value returned by the function.</p>
				<pre><code>return number * number;</code></pre>
				<p>Primitive parameters (such as a number) are passed to functions by value; the value is
				passed to the function, but if the function changes the value of the parameter, this change is
				not reflected globally or in the calling function.</p>
			</article>
		</section>
	</main>
	<nav id="navbar">
		<header class="nav_header">
			JavaScript Documentation
		</header><br>
		<ul class="navlist">
			<li>
				<a class="nav-link" href="#Introduction">Introduction</a>
			</li>
			<li>
				<a class="nav-link" href="#What_you_should_already_know">What you should already know</a>
			</li>
			<li>
				<a class="nav-link" href="#JavaScript_and_Java">JavaScript and Java</a>
			</li>
			<li>
				<a class="nav-link" href="#Hello_World">Hello World</a>
			</li>
			<li>
				<a class="nav-link" href="#Variables">Variables</a>
			</li>
			<li>
				<a class="nav-link" href="#Declaring_Variables">Declaring Variables</a>
			</li>
			<li>
				<a class="nav-link" href="#Variable_Scope">Variable Scope</a>
			</li>
			<li>
				<a class="nav-link" href="#Global_Variables">Global Variables</a>
			</li>
			<li>
				<a class="nav-link" href="#Constants">Constants</a>
			</li>
			<li>
				<a class="nav-link" href="#Data_Types">Data Types</a>
			</li>
			<li>
				<a class="nav-link" href="#If...else_Statement">If...else Statement</a>
			</li>
			<li>
				<a class="nav-link" href="#While_Statement">While Statement</a>
			</li>
			<li>
				<a class="nav-link" href="#Function_Declarations">Function Declarations</a>
			</li>
		</ul><br>
	</nav><br>
	<footer>
		Designed and Coded by: <a href="https://codepen.io/hatbearingoctopus/" target=
		"_blank">Hatbearingoctopus</a>
	</footer>
</body>
</html>
              
            
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CSS

              
                

/* The sidenav */

#navbar {
	height: 100%;
	width: 200px;
	position: fixed;
	z-index: 1;
	top: 0;
	left: 0;
	background-color: #94b8b8;
	overflow-x: hidden;
	padding-top: 10px 10px 10px 25px;
}
.nav-link {
	text-decoration: none;
	font-family: 'Aldrich';
	border-top: 1px;
	cursor: pointer;
}
.navlist {
	list-style-type: none;
}
.nav_header {
	font-family: 'Aldrich';
	text-align: center;
	text-decoration: underline;
	line-height: 1.75;
	font-size: 1.25em;
	padding: 10px;
}
/* Style the links inside the navigation bar */

#navbar a {
	float: left;
	display: block;
	color: #f2f2f2;
	text-align: left;
	padding: 12px;
	font-size: 1em;
}
/* Change the color of links on hover */

#navbar a:hover {
	background-color: #ddd;
	color: black;
}
h1 {
	font-family: 'Aldrich';
	font-size: 2.5em;
	text-decoration: underline;
	margin-left: 230px;
}
h3 {
	font-family: 'Aldrich';
	font-size: 1.5em;
}
code {
	display: block;
	text-align: left;
	white-space: pre;
	line-height: 2.5;
	background-color: #e0ebeb;
	padding: 15px;
	margin: 10px;
	color: #000099;
	border-radius: 5px;
}
/* Page content */

.main-section {
	font-family: 'Asap';
	font-size: 1.25em;
	margin-left: 230px;
	/* Same as the width of the sidenav */
}
footer {
	font-family: 'Aldrich';
	font-size: 1em;
	margin-left: 230px;
}
/*responsively scale text */

@media only screen and (max-width: 320px) {
	body {
		font-size: 2em;
	}
}
/* On smaller screens, where height is less than 450px, change the style of the sidenav (less padding and a smaller font size) */

@media screen and (max-height: 450px) {
	.nav-link {
		padding-top: 15px;
	}
	.nav-link a {
		font-size: 18px;
	}
}
              
            
!

JS

              
                
              
            
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999px

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