Ajax

The term Ajax describes an architecture for web applications that prominently features
scripted HTTP.

Ajax描述了一种web应用的架构，这种应用以脚本化HTTP为特点。

The key feature of an Ajax application is that it uses scripted HTTP
to initiate data exchange with a web server without causing pages to reload.

ajax应用的主要特点是它使用脚本化HTTP与服务器进行数据交换，而不需要导致页面重载。

The ability to avoid page reloads (which were the norm in the early days of the Web) results in

responsive web applications that feel more like traditional desktop applications.

避免页面重载的能力使响应式应用更像桌面应用。

A web
application might use Ajax technologies to log user interaction data to the server or to
improve its start-up time by displaying only a simple page at first and then downloading
additional data and page components on an as-needed basis.

应用可以用ajax技术将用户交互信息存到服务器，或提升它的启动时间，通过在开始只显示一个简单的页面，然后在需要的时候下载额外数据和页面组件。

The term Comet refers to a related web application architecture that uses scripted
HTTP.

comet 指一种相关的应用架构，这种架构可以用校本化HTTP。

In a sense, Comet is the reverse of Ajax: in Comet, it is the web server that
initiates the communication, asynchronously sending messages to the client.

某种意义上，comet 和ajax 相反。在comet中，服务器发起交流，异步向客户端发送信息。

If the web
application needs to respond to these messages sent by the server, it can then use Ajax techniques to send or request data.

如果应用需要回应这些信息，它可以用ajax技术发送或请求数据。

In Ajax, the client “pulls” data from the server. With
Comet, the server “pushes” data to the client. Other names for Comet include “Server
Push,” “Ajax Push,” and “HTTP Streaming.”

在ajax中，客户端从服务器拉取数据。在comet中，服务器向客户端推送数据。comet的其他名字包括：服务器推送，ajax推送，http流。