Xml , namely extensible markup language , is a markup language which is now widely applied in web service area . it can mark up any content and data . for computers , computers can transfer and handle data via xml labels 、 attributes and contents ; for programmers , programmers can program and handle data with very readable labels . therefore , for both computers and programmers , xml is the most convenient matter for data processing . web service realizes internet service invoking which is based on soap 、 uddi etc . technologies , and these technologies are based on xml . web service is a software interface , which describes a group of operations which can be visited via standardized xml message transfer . it uses xml - based protocols to describe the operations or the data that will be exchange with another web service Xml ( extensiblemarkuplanguage ) ,即可扩展标记性语言,是当前广泛地应用于webservice领域的标记语言,它能对各种内容、数据进行标记。对计算机而言,通过对标签、标签属性及标签内容的识别,可以对数据进行转换、处理;对编程人员而言,通过具有很强可读性的标签,可以非常方便的对数据进行编程处理,因此,对人和计算机而言, xml都是进行数据处理最方便的方式。 webservice是以soap 、 uddi等技术为基础,实现internet上的服务调用,而soap 、 uddi等都是以xml为基础的。