Well this information might be very usefull for those , who still dont know about it and that is why im posting this post 
Modern web sites and applications use Ajax to create engaging user experiences: the HTML and CSS are set in motion using JavaScript running in the browser and calling back the server. To achieve this, the server needs to prepare the web page appropriately, and to know what to do when the JavaScript calls it. But the server knows nothing about the HTML and CSS DOM, nor how to handle JavaScript data, and you can’t code it in JavaScript…
…Jaxer changes all that. Jaxer is the world’s first true Ajax server. HTML, JavaScript, and CSS are native to Jaxer, as are XMLHttpRequests, JSON, DOM scripting, etc. And as a server it offers access to databases, files, and networking, as well as logging, process management, scalability, security, integration APIs, and extensibility.
Write entire applications or presentation layers in Ajax
Your client code, your server code, and even shared code can all be written using the Ajax skills you already have. True “single page applications” are now possible, as well as full-featured end-to-end-Ajax web applications and rich presentation layers against your current back-end.
Write entire applications or entire presentation layers in Ajax
Full DOM and JavaScript on the server
Because Jaxer is a full Ajax server, you can not only run JavaScript on the server using the same techniques you’ve mastered in the browser, but you can also manipulate the DOM in the APIs you already use — and you can even use Ajax libraries like jQuery on the server side.
Full, standard, scriptable HTML DOM and JavaScript on the server
Seamless communications between browser and server
Accessing server-side JavaScript functions is as easy as calling any browser-side function. Just call them as you normally would, same parameters, same return values — all of the data marshaling and communications is transparently handled for you. You can designate functions to run on the server and call them synchronously or asynchronously (by just adding “Async” to their name and specifying a callback).
Call server JavaScript functions from the browser
Access existing pages written in other languages like PHP, Java, or Ruby on Rails
Jaxer includes a rich framework for many useful tasks on the server, including accessing local or remote web resources and services without cross-domain security restrictions that a browser might impose, or rewriting HTML pages generated by other platforms.
Access existing resources served by other languages like PHP, Java, or Ruby on Rails
Share validation code on the browser and server
With Jaxer, you can also tag any function or block of functions to run on both the server and the browser. Developers can write logic once, and it can be executed from either location. One ideal use of this is data validation. Validate your forms on the client to provide instant user feedback, and once the form is successfully submitted, validate it again on the server to ensure its integrity, using the exact same logic — no more code rewriting, and no getting them out of sync and possibly opening security holes.
Share validation code on the browser and server
Database, file, and socket access from JavaScript
With Jaxer, your JavaScript gains full access to databases such as MySQL or the integrated SQLite database. Rich filesystem I/O as well as low-level network socket access are available to you all directly in JavaScript on the server. And you can call those server functions seamlessly from the client — exposing only the ones consistent with your security requirements.
Database, file, and socket access
Open-source, standards-based, and uses the APIs you already know
Jaxer is licensed under the GPL, and leverages the ubiquitous Mozilla engine that is used in Firefox 3, which means that Jaxer is fully compatible with the latest JavaScript standards, including access to all of the features you are familiar with — from Date to Math to window and document, and even JavaScript 1.5, 1.7, and 1.8 — they’re all there. If you know JavaScript and HTML, you can already build Jaxer applications.
Open source, standards-based, and uses the APIs you already know
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