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What is jQuery?

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Video transcript

jQuery is the most popular library on the web today. It's a library of JavaScript functions that make it easy for webpage developers to do common tasks-- like manipulating the webpage, responding to user events, getting data from their servers, building effects and animations, and much more. jQuery builds on top of the functionality that browsers give us via the JavaScript DOM API, but lets us accomplish the same things in fewer lines of code. For example, let's say you wanted to resize all of the images on your page, like when the user clicked a button. You could write these four lines of code here, and that would work. Or, you could write this single line of code, and jQuery will do all the heavy lifting for you. Plus, jQuery takes care of any cross-browser bugs or inconsistencies. In 2014, over 60 percent of the top million webpages included jQuery. So, pretty much all web developers either know jQuery, or have used jQuery at some point in their career. And now you can become one of those developers.