第四单元第五单元万维网是一个查找并使用网络资源的基于超文本系统。
?The world wide web is a hypertext-based 基于超文本的 system for finding and accessing Internet 查找并使用resources;万维网由一系列程序、标准以及协议组成，其作用是管理多媒体文件在网上创建和显示的方式。
it is a set of programs, standards, and 一系列 protocols governing the way in which 管理 multimedia files are created and displayed on the Internet.It can provide access to a variety of Internet resources from the same interface, includingFTP, Gopher, groups in addition to HTTP它提供从相同的接口访问不同网络资源(的功能)，除了HTTP网站，还包括FTP、Gopher。
?sites.The world wide web is a distributed, multimedia and hypertext system, and thus a 万维网是一个分布式的多媒体超文本系统，因此是一个用于交流和发布的独特媒介。
unique medium for communications and for 媒介交流、沟通 publishing. 发布The ability( to jump from one documents to the next ) is made possible through the use ofhyperlinks.通过使用超链接来实现从一个文档跳转至另一个文档的功能。
?By clicking on the hyperlink, the user is immediately connected to the document (specified by the link).通过点击超链接，用户可以立刻连接到该超链接所指的文件。
?The explosion (in use) and popularity (of the Internet in the 1990s) was most likely due to be due to:由于、起因于 the graphics-intensive nature of the World 特性、特质 Wide Web. ?因为万维网大量的图像化特质，在1990年代， Internet网被广泛利用，大受欢迎。
…which is used to send written messages文本消息between individuals or groups of individuals,often geographically separated by largeEmail的作用是在远隔千里的个人或团体之间传递文本消息。
?distances.As a very convenient and inexpensive way to?transmit message, email has dramaticallyaffected scientific, personal, and businesscommunications.作为一个方便廉价的传递消息的方式，email大大影响了科技、个人、商业的通信。
Ecommerce has grown out of business that started to advertise their presence via a Web电子商务起源于那些通过网站进行广告宣传的商业活动。
sites.The costs of commercial transactions arenegligible, compared with using the与使用传统分发和零售网络相比，（通过电子商务的）商业交易成本几乎可忽略。
?traditional distribution and retail network.What is more revolutionary is that the Web can lead to greater political involvement in 导致、引发参与、卷入 decision making for ordinary people, for决策制定更具有创新价值的是，网络让普通民众有更多机会参与到政治的决策制定中去，如通过电子投票系统。
?example, via e-voting systems.Web technology has also been extended to handle conferencing and real-time communications, to enable the Web to act like groupware, which facilitates people 组件 collaborating over a network, especially over and intranet.网络技术已经扩展到处理会议和实时通信，这令网络成为一个团体，从而促进人们通过网络，特别是内网进行协作。
第六单元多媒体是信息技术行业最令人着迷的最快速的增长领域之一。
?Multimedia is one of the most fascinating 令人着迷的 and fastest growing areas in the field of 增长领域行业 Information Technology.多媒体一词用来描述一系列多样化的技术，多媒体为通信提供了一种将视觉、听觉媒体结合在一起的全新方式。
The term “multimedia”describes a number of diverse technologies (that allow visual and 多样化的 audio media to be combined in new ways for the purpose of communications.)学校也许最需要多媒体的高效和有力。
Schools are perhaps in the direst need of the 需要 effectiveness and power of multimedia. 高效有力Using multimedia software or presentations is a great way to introduce new concepts and使用多媒体软件或演示，是向学生介绍新概念和技术的良好方法。
technologies to students.多媒体将文本、声音、图像、视频和动画简单的绑定在一起，形成了一个强有力的工具，特别是对学生来说。
Multimedia simply combines text, sound, graphics, video and animation into a 动画 powerful new tool, especially in the hands of students. 利用多媒体，诸如文本处理器或者电子表格这样的基本办公软件也会成为商业上的有力工具。
With multimedia, even a basic office application such as a word processor or a 办公软件文本处理器 spreadsheet becomes a powerful tool for 电子表格 business. Pictures, animation and sound can be added to these applications, emphasizing important points in the documents.这些软件可通过添加图片、动画和声音来强调文件中的重要点。
在商业中，视频会议是另一个重要的多媒体应用。
视频会议使用计算机网络来传递音频、视频数据，使得身处不同地点的多个参加者可以召开会议。
? Another important practice of multimedia in business is videoconferencing, (which conducts a conference between two or more participants at different sites by using computer network to transmit audio and video data.) ?多媒体利用更多增强的感受和经历来使创新和交互的游戏成为可能，这些游戏带来令人沉醉的音效和炫目的画面。
? Multimedia makes possible innovative and interactive games with greatly enhanced feeling and experience, which just come alive with immersive sounds and dazzling graphics. ?为建筑多媒体工程设定的基本工具包括多个编著系统和各种不同的文本、图像、声音和视频编辑软件。
? The basic tool （set for building multimedia projects ）contains oneor more authoring systems and various editing applications for text, images, sounds and videos.另一些工具可用来进行屏幕图像捕捉，转换文件格式，为团队合作在多个电脑中移动文件。
?A few additional applications are also useful for capturing images from the screen, translating file formats, and moving files among computers for the sake of teamwork.第七单元嵌入式系统是一个专用的系统，计算机被其所控?An embedded system is special-purpose system （in which the computer is completely encapsulated by the device it controls. ）封装 the computer controls制的设备完全的封装起来。