Key difference: jQuery is a multi-browser JavaScript library. jQuery is a free, open source software. It is licensed under the MIT License. It was designed to simplify the client-side scripting of HTML and is currently used by numerous websites. .ajax() and .load() are two different commands that can be used to access jQuery. jQuery.ajax() performs an asynchronous HTTP (Ajax) request. It gives the user the most control. $.load is a helper function which only can be invoked on elements. It loads data from the server and places the returned HTML into the matched element.

jQuery is a multi-browser JavaScript library. jQuery is a free, open source software. It is licensed under the MIT License. It was designed to simplify the client-side scripting of HTML and is currently used by numerous websites. In fact, according to Wikipedia, it is used by over 55% of the 10,000 most visited websites. It is the most popular JavaScript library in use today. jQuery was released in January 2006 at BarCamp NYC by John Resig. However, it is currently developed by a team of developers led by Dave Methvin.

jQuery's syntax is designed to make it easier to navigate a document, select DOM elements, create animations, handle events, and develop Ajax applications. In addition to the JavaScript library, jQuery also provides capabilities for developers to create plug-ins. The advantage of this is that it enables developers to create abstractions for low-level interaction and animation, advanced effects and high-level, theme-able widgets. Furthermore, the approach to the jQuery library allows the creation of powerful dynamic web pages and web applications.

jQuery is a JavaScript library, which is extensible by a plugin mechanism. jQuery is a framework which is built in JavaScript in order to help programmers who work with common web tasks. jQuery exposes a number of utility functions that make programming in JavaScript easier. jQuery aims to make it easier for the programmers rather than have them work in raw JavaScript. It achieves this by extending the functionality of JavaScript.

jQuery also makes HTML document traversal and manipulation, event handling, animation, and Ajax much simpler with an easy-to-use API that works across a multitude of browsers.

.ajax() and .load() are two different commands that can be used to access jQuery. Essentially, $.get(), $.post(), .load()are all just wrappers for $.ajax(). Also, .ajax and .get are practically the same thing and have the same result.

jQuery.ajax() performs an asynchronous HTTP (Ajax) request. It gives the user the most control. It is the most configurable one. It provides the user with fine grained control over HTTP headers and such. It also allows direct access to the XHR-object. It allows the user to specify if they want to POST data, get more callbacks, etc. It also provides a slightly more fine-grained error-handling. It is often considered as being more complicated and often unnecessary; however it can be very useful at times.

$.load is a helper function which only can be invoked on elements. It loads data from the server and places the returned HTML into the matched element. It is similar to $.get() but adds functionality. This functionality allows the user to define where in the document the returned data is to be inserted. Hence, the .load() is only usable when the call will result in HTML. It is a method tied to a particular jQuery-wrapped DOM element, therefore it is called slightly differently than the other global calls.

Unlike $.ajax, $.load has a much more specific purpose; a higher-level. $.ajax, on the other hand, is a low-level function. It accepts many more arguments, and as such, can be set to mimic the behavior of $.load, or many other high-level AJAX functions such as $.get and $.post.

In layman’s terms, .load() loads a webpage from the server, and places the output into an element on the page, whereas .ajax() loada a webpage from the server, and decides what to do with the output. It also provides several additional advanced options.

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