引言网际网路（Ｉｎｔｅｒｎｅｔ）连接著成千上万的电脑，使得人们可以籍著网际网路互通讯息、撷取资料、交换音乐甚至上网聊天，全部都是很炫的功能。而且网路无远弗届的能力，让远在世界各地的人们，都能简单的打破了距离的藩蓠。网路的方便性、国际性和普遍性，一再的显示 INTRODUCTION The internet connects thousands of computers, making it possible for people to share information, retrieve data, exchange music and even surf the Internet on the Internet, all of which are cool features. Moreover, the ability of the Internet to reach beyond its limits makes it possible for people in all parts of the world to simply break away from the fanciful. The convenience, internationality and universality of the Internet have been repeatedly demonstrated