JavaScript, jquery, Ajax summary

Actually before the study. has already used the Js,jquery and Ajax, just did not know these differences, all as JS to see. Then others say jquery. Ajax thinks it seems very advanced. Wait until you learn, it is a little clearer about these, to write my summary below.

Simple Introduction
Javascript

JavaScript, a literal-translation scripting language. is a dynamic type, prototype-based language. Built-in support classes.

Its interpreter is called the JavaScript engine and is part of the browser. The scripting language, which is widely used in the client, was first used on HTML pages to add dynamic functionality to HTML pages. Today, however, JavaScript can also be used for Web servers. such as node. js.

In 1995, the Brandon Aick of Netscape was first designed and implemented on the Netscape Navigator's browser.

Because of the marketing cooperation between Netscape and Sun Yang, and the Netscape management wants it to look like Java, it is named JavaScript. But in fact its semantics are closer to self and scheme.

In order to gain technical advantage. Microsoft has introduced JScript, which is the same as JavaScript and can be executed on the browser.

In order to unify the specifications, 1997, under the coordination of the ECMA (European Association of Computer manufacturers). A working group consisting of Netscape, Sun, Microsoft and Borland established a unified standard: ECMA-262. Because JavaScript is compatible with the ECMA standard, it is also known as ECMAScript.

Juery

jquery is a set of cross-browser JavaScript libraries that simplifies the operation between HTML and JavaScript. The first version number was announced by John Ressig John Resig on the BarCamp NYC in January 2006. This is now being developed by the development team led by Dave Methvin. The top 10,000 most visited sites in the world. 65% uses jquery, which is now the most popular JavaScript library.

AJAX

Ajax, "Asynchronous JavaScript and XML" (Asynchronous JavaScript and XML technology), refers to a set of browser-side web development techniques that combine a number of technologies.

[1] The concept of Ajax is presented by Jessi James Jarrett.

Traditional Web applications agree to fill out forms (form) on the client side. A request is sent to webserver when the form is submitted.

The server receives and processes the incoming form and then sends it back to a new Web page, but this practice wastes a lot of bandwidth. Since most of the HTML code in the front and back two pages is often the same. Because each application communication needs to send a request to the server. The response time of the application depends on the response time of the server. This causes the user interface to respond much more slowly than the native application.

Unlike this, AJAX applications can send and retrieve only the necessary data to the server, and the client uses JavaScript to handle the response from the server.

Because the amount of data exchanged between the server and the browser is much lower (about only 5% of the original) [the source requests the],server response faster. At the same time, a lot of processing can be done on the client machine that made the request, so the load on the webserver is reduced.

Similar to DHTML or Lamp,ajax does not refer to a single technique, but rather organically utilizes a range of related technologies. Although its name includes XML, the data format can actually be replaced by JSON, further reducing the amount of data to form so-called Ajaj. Neither client nor server needs to be asynchronous. Some Ajax-based "derivation/composition" (Derivative/composite) technologies are also emerging, such as Aflax.

difference

From a brief introduction we can see. JavaScript is a scripting language, and jquery is the encapsulation of JS, Ajax is a very diverse mix of technology, their differences are very obvious. But they all provide a simpler technique for our program.

Summary
JavaScript

   Jquery+ajax

Very often the fact that watching a video directly is not good, and is usually caught in a kind of, this is what the situation, this time. A little bit more code. The simple error effect is better, and will certainly be knocked out at the start. Knock more slowly know how to use, of course, after the practice, still need to go back to the theory to learn ~

JavaScript, jquery, Ajax summary