What Does the Dollar Sign ($) Mean in JavaScript?

Understanding the Role of "$" in JavaScript

In JavaScript, the dollar sign ($) is often used in conjunction with JavaScript libraries. In the provided code snippet:

$(window).bind('load', function() {
    $('img.protect').protectImage();
});

The "$" is used for the following purposes:

Function Call

In the snippet, the $ is preceded by parentheses and followed by a function call. This indicates that the $ is being used as a function. In this case, it is likely a method from a JavaScript library such as jQuery.

Object Access

The $ can also be used to access objects or properties. For example, $('img.protect') likely retrieves a collection of elements with the class name protect.

Shortcut for jQuery

Many JavaScript libraries, including jQuery, use the $ as a shortcut for the library's primary object or function. For example, $ is commonly used in place of jQuery.

Validity as an Identifier

It's important to note that $ is a valid JavaScript identifier. This means that it can be used to name variables, functions, or objects. However, the use of $ as an identifier may conflict with JavaScript libraries that utilize it.

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