Edit in JSFiddle

var str1 = 'single quote';
var str2 = "double quote";

document.write(str1);
document.write("<br/>");
document.write(str2);

<h1>String</h1>

<h2>String Quotes</h2>

<p>Strings can be enclosed within either single quotes, double quotes.</p>

<blockquote>
var str1 = 'single quote';<br/>
var str2 = "double quote";
</blockquote>