categorized as personal computer, handheld computers, workstations, mainframes, supercomputers , and servers.
大多数人可以制订一个电脑精神的图片，但电脑做很多事情，出现这样的形状和大小不同，它似乎难以提炼成一个全能的定义，它们的共同特点。在其核心，一台计算机是一种装置，它接受输入，处理数据，存储数据，并产生输出，根据对所有存储一系列指示。 什么是计算机输入到计算机系统的压力。输入可提供的一人，由环境，或由另一台计算机。对输入的各种例子，一个计算机可以接受包括文字和符号的文件，规定计算，图片，从恒温器的温度数字，音频信号从一个麦克风，从电脑程序指令。一个输入设备，如键盘或鼠标，集输和转换成一个电子信号的计算机的一系列。
在计算中，数据是指以符号代表的事实，对象和想法。计算机操作在很多方面的数据，我们称之为操作处理。一系列的指令，告诉计算机如何进行处理任务，被称为一个计算机程序，或只是一个“程序”。这些方案形成了软件，建立了计算机做特定的任务。在计算机中，大部分处理发生在一个组件的地方称为中央处理单元（CPU），有时为“大脑的计算机”来形容。
计算机存储数据，以便它会被用作处理可用。大多数计算机有多个用于存储数据的位置，这取决于数据如何被使用。内存是计算机的一个领域，数据是暂时持有等待处理，存储或输出。在数据存储，是可以在一个地区长期离开时，没有立即处理所需。
输出是由电脑产生的结果。电脑输出的一些例子包括报告，文件，
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音乐，图形，图片。输出设备显示，打印，或传送的处理结果。 电脑是多功能机，它能够执行各种各样的任务十分惊人，但某些类型的计算机更适合比其他类型的计算机的某些任务。计算机可以被归类为个人电脑，掌上电脑，工作站，大型机，超级计算机和服务器。
A personal computer is a type of microcomputer, designed to meet the computing needs of an individual. It typically provides access to a wide variety of computing applications, such as word processing, photo editing, e-mail, and Internet access. Personal computers are available as desktop computers or notebook computers. 个人计算机是一种微型计算机，它能够满足个人的计算需要，它特别提供了适应各种各样计算应用的方法，比如说文字处理、相片编辑、电子邮件以及进入互联网，个人计算机可以被当作台式计算机以及笔记本电脑一样使用 A handheld computer is designed to fit into a pocket, run on batteries, and be used while you are holding it. Also called a PDA (Personal Digital Assistant) and a palmtop computer, a computer in this category is typically used as an electronic appointment book, address book, calculator, and notepad. With its slow processing speed and small screen, a handheld compute is not powerful enough to handle many of the tasks that can be accomplished by desktop or notebook personal computers. A handheld computer is designed to bea computing accessory, rather than your primary computer掌上电脑被设计成能够放
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进口袋，能依靠电池工作，并且当你放在手上它时能够运行。它也被称作PDA（个人数字助手）和手掌上的电脑，这种类型的计算机典型性地被作为电子图书、通讯录、计算器以及记事本来使用。由于其速度较慢且显示屏较小，所以掌上电脑功能不够强大无法执行台式计算机及个人电脑所能完成的很多任务。掌上电脑旨在成为计算助手而非成为你的主要计算机。
Computers advertised as workstation are usually powerful desktop computers designed for specialized tasks. A workstation can tackle tasks that require a lot of processing speed, such as medical imaging and computer-aided design. Some workstations contain more than one microprocessor, and most have circuitry specially designed for creating and displaying three-dimensional and animated graphics . Because of its cost, a workstation is often dedicated to design tasks, and is not used for typical microcomputer applications, such as word processing, photo editing, and accessing the Web. 被人们大力宣传为工作站的计算机通常是指设计来完成特定任务的功能强大的台式计算机。工作站能够处理需要快速处理的任务，例如医学成像以及计算机辅助设计。某些工作站包含不止一个微处理器，并且大多数具有特别为产生和显示三维和动画图像而设计的电路。由于其成本高，所以一个工作站通常用来设计任务，而不是用来作为典型的微型计算机来应用，例如文字处理、图像编辑以及网络访问
Ordinary personal computers that are connected to a local area
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network can also be called as workstations. A computer network is two or more computers and other devices that are connected for the purpose of sharing data and programs. A LAN (local area network) is simply a computer network that is located within a limited geographical areasuch as a school computer lab or a small business与局域网相连接的普通的个人计算机也可以被称为工作站。计算机网络是由两台或多台计算机以及其它连接在一起为了共享数据和程序的设备而组成的。一个LAN（局域网）仅仅是一个限定地理区域内的计算机网络，例如一个学校计算机实验室或一个小商行。
A mainframe computer ( or simply a \mainframe\ expensive computer that is capable of simultaneously processing data for hundreds or thousands of users. Mainframes are generally used by businesses or governments to provide centralized storage, processing, and management for large amounts of data. Mainframes remain the computer of choice in situations where reliability, data security, and centralized control are necessary. 主机（或简写为“mainframe”）是一种大型昂贵的能够同时为成百上千用户处理数据的计算机。主机通常由商行或政府使用用来提供对大量数据的集中存储、处理以及管理。主机使我们在需要可靠性、数据安全性以及集中处理的情况下提供了可选择的计算机。
A computer falls into the supercomputer category if it is, at the time of construction, one of the fastest computers in the world. Because of
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their speed, supercomputers can tackle complex tasks that just would not be practical for other computers. Typical uses for supercomputers include breaking codes, modeling worldwide weather systems, and simulating nuclear explosions. One impressive simulation designed to run on a supercomputer tracked the movement of thousands of dust particles as they were tossed about by a tornado如果某种计算机在其制造的时代是世界上最快的计算机之一，那么这种计算机就属于超级计算机类型。由于它们的速度，超级计算机能够处理其它计算机所不能处理的复杂任务。超级计算机的典型的作用包括破解密码、建立世界范围的天气系统模型以及模拟核爆炸。超级计算机上所完成的一个使人留下深刻印象的仿真是对数以千计的尘埃微粒的运动进行追踪，这些尘埃微粒就象被一场龙卷风所抛掷一样。
In the computer industry, the term \server\can refer to computer hardware, to a specific type of software, or to a combination of hardware and software. In any case, the purpose of a server is to \a LAN ) by supplying them with data. A personal computer, workstation, or software that requests data from a server is referred to as a client. For example, on a network, a server might respond to a client's request for a Web page. Another server might handle the. steady stream of e-mail that travels among clients from all over the Internet. A server might also allow clients within a LAN to share files or access a centralized printer.
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