This Section
Introduction of computer development
Computer hardware
The basic principles of computer
computer
In today's era, society has entered the era of the fourth industrial revolution. In this day and age, computers are the most common tools. Computer (computer) also commonly known as computer. A method for modern high-speed computation of computer device that can be numerical, but can be logically calculated, further having a memory function. Is a modern intelligent electronic devices capable of running in accordance with the automatic, high-speed processing of massive data.
Hardware and software systems composed of, without any software installed called bare computer. Can be divided into supercomputers, industrial control computers, network computers, personal computers, embedded computers five categories, more advanced computers have biological computers, computer photon, a quantum computer. Computer inventor John von Neumann.
The computer is one of the most advanced scientific and technological invention of the 20th century, production of human and social activities had a very important influence, with strong vitality and rapid development. Its applications extend from the initial military research applied to all areas of society, has formed a huge scale computer industry, driven by technological progress worldwide, which led to profound social change, the computer has been throughout the general schools, companies institutions, into the homes of ordinary people, has become an indispensable tool in the information society.
Use of computers is increasingly common in China, reform and opening up, the number of Chinese computer users continue to rise, applications continued to improve, especially in the field of application of the Internet, communications, multimedia and achieved good results. In 1996-2009, the number of computer users increased from 6.3 million to 67.1 million units of the original, the number of networked computers increased from 29 000 bench rose to 59.4 million units. Internet users has reached 316 million, there are 670 million mobile wireless Internet users, mobile Internet users reached 117 million, is the first in the world.
Development History
Calculation tool evolution experienced from simple to complex, different stages from lower to higher, for example,
ENIAC computer
The chip count from the "Jieshengjishi" in the knot, slide rule calculations, mechanical computers. They play their respective roles in the history of different historical periods, but also inspired the development of the modern computer is thinking.
ENIAC computer
In 1889, American scientist Herman Hollerith developed electricity-based electric tabulating machine to store calculations.
In 1930, American scientist Vannevar Bush made the world's first analog computer.
February 14, 1946, customized by the US military in the world's first computer "Electronic Numerical Integrator and Computer" (ENIAC Electronic Numerical And Calculator) at the University of Pennsylvania come out. ENIAC (Chinese name: Eni Ake) US Oberding weapons test site in order to meet computing needs of research into ballistic, this calculator uses the 17840 tubes, size 80 feet × 8 feet and weigh up to 28t ( tons), power consumption of 170kW, the operation speed of 5,000 times per second adder, cost about $ 487,000. ENIAC advent of epoch-making significance, suggesting that the era of the computer. After 60 years, computer technology development at an alarming rate, there is no cost-effective technology can be a growth of six orders of magnitude in 30 years.
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1st generation: digital tube machine (1946-1958 years)
Hardware, logic elements uses a vacuum tube, the mercury in the main delay line memory
Tube digital computer
Cathode ray oscilloscope static memory, magnetic drum, a magnetic core; external memory employed tape. Software uses a machine language, assembly language. Military applications and scientific computing based.
Tube digital computer
It characterized by bulky, high power consumption, poor reliability. Slow (typically thousands to tens of thousands of times per second), the price is expensive, but it laid the foundation for the future development of the computer.
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Second generation: digital transistor machine (1958-1964 years)
Hardware, operating systems, and high-level language program to compile scientific computing applications and transaction-based, and began to enter the field of industrial control. Characterized by the volume reduction, reducing energy consumption, improving the reliability, operation speed (typically the number of 100,000 times per second, up to 3 million), performance is greatly improved over the first generation computer.
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3rd generation: integrated circuit digital machine (1964-1970 years)
Hardware, logic elements employed in small scale integrated circuits (MSI, SSI), a main memory core still employed. The emergence of software as well as time-sharing Caozuoxitong structure, large-scale programming method. Characterized by faster (typically millions to tens of millions of times per second), and reliability have been significantly improved, a further decline in prices, products to the general, serialization and standardization. Applications began to enter the word processing and graphics image processing.
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4th generation: LSI machine (1970-present)
Hardware, logic elements using the scale and ultra large scale integrated circuit (LSI and VLSI). Software emergence of database management systems, network management systems and object-oriented language. In 1971 the world's first microprocessor was born in Silicon Valley in the United States, creating a new era of the microcomputer. Applications from scientific computing, transaction management, process control gradually the family.
Since the development of integrated technology, higher integration of the semiconductor chips, each chip can accommodate tens of thousands or even millions of transistors, and may be the operator and the controller are concentrated on a single chip, which appeared microprocessor, and can be used microprocessors and large-scale, ultra large scale integrated circuits assembled into a microcomputer, is what we often say microcomputer or PC. Microcomputers small, cheap, easy to use, but its functionality and speed of operation have been met or exceeded in the past mainframe computers. On the other hand, the use of large-scale, ultra large scale integrated circuit manufacturing various logic chips, has made the volume is not large, but the computing speed of up to one hundred million or even billions of times a supercomputer. Following our successful development after 1983 operations per one hundred million times that of the Milky Way Ⅰ type supercomputer, has developed a successful operation in 1993, billions of times per second type Ⅱ Galaxy general-purpose parallel supercomputers. This period also spawned a new generation of programming languages and database management systems and network software.
With the physical dollar, changes in the device, not only the host computer has gone through upgrading its external devices are constantly change. For example an external memory, displayed from the initial development of the cathode ray tube to the core, drum, and later development of a universal disk, now appeared smaller, larger, faster read-only optical disk (CD-ROM ).
era
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period
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time
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Typical computer
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description
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First computers
(tubes) |
Nian 1946
2 Yue 16 Ri |
ENIAC
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The University of Pennsylvania developed a real sense of the history of mankind's first computer, an area of 170 square meters, power 150 kilowatts, cost $ 4.8 million, or perform addition or 5000 times per second, 400 multiplications. 18000 tubes were used.
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1950
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EDVAC
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Two first parallel computer, the father of the computer implemented. "Von Neumann" scenario: binary and storage procedures.
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Second generation computer
(transistor) |
1954
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TRADITIONS
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The first computer using a transistor manufactured by IBM, the floating point increases, so that the computing power has been greatly improved
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1958
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IBM 1401
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This is representative of the second generation of computers, the user then can be rented.
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Third-generation computers in 1964 began to appear in the 1960s IBM360 further development of computer software technology, especially matures Caozuoxitong is a distinctive feature of the third generation of computers.
(Integrated circuit) at the end of mass production. (1964-1971)
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period
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time
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Typical computer
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description
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The fourth generation of computers (large-scale and ultra large scale integrated circuit)
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1970
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IBM S/370
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This is an important product of IBM replacement, instead of using the LSI core memory, small-scale integrated circuits as logic elements, and the use of virtual memory technology, hardware and software will be separated, and thus clear the value of the software.
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April 1975
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Altair 8800
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MITS manufactured with 1KB memory. This is the world's first microcomputer.
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April 1977
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Apple II
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NMOS6500 1MHz CPU, 4KB RAM 16KB ROM, which is a history of the personal computer with color graphics computer
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August 12, 1981
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IBM PC
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采用了主频为4.77MHz的Intel 8088CPU，内存64KB,160KB软驱，操作系统是Microsoft提供的MS-DOS
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1983年1月19日
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APPLE LISA
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第一台使用了鼠标的电脑，第一台使用图形用户界面的电脑。
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1983年3月8日
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IBM PC/XT
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采用INTEL8088 4.77MHz的CPU，256K RAM和40K ROM,10MB的硬盘，两部360KB软驱。
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1984年8月
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IBM PC/AT
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采用Intel 80286 6MHzCPU， 512KB内存，20MB硬盘和1.2M软驱。
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1986年9月
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Compaq Desktop PC
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采用了Intel 80386 16MHz CPU,640KB内存，20MB硬盘，1.2M软驱，是计算机史上第一台386计算机。
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1989年4月
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DELL 80486
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采用Intel 80486DX CPU 640KB内存， 20MB硬盘，1.2M软驱。
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1996年
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基本配置是奔腾或者奔腾MMX 的CPU，32M EDO或者SDRAM内存，2.1G硬盘，14寸球面显示器为标准配置。
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1997年
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基本配置开始向赛扬处理器过渡，部分高档的机器开始使用PentiumII CPU，同时内存也由早期的EDO过渡到SDRAM，4.3G左右的硬盘开始成为标准配置。
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1998年
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带有128K二级高速缓存的赛扬处理器成为广大装机者的最爱，同时64M内存和15寸显示器开始成为标准配置。
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1999年
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部分品牌厂商开始将PentiumIII CPU作为电脑的一个卖点，64M内存和6.4G硬盘开始成为电脑的标准配置。
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2000年
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66M和100M外频的赛扬处理器占领了大部分品牌或兼容机的市场，128M内存，10G以上的硬盘开始成为标准配置，17寸显示器慢慢进入家庭。
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2001年至今
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Pentium 4 CPU和Pentium 4赛扬CPU开始成为电脑的标准配置，内存由SDRAM实现了向DDR的过渡，同时17寸CRT显示器或者15寸液晶显示器开始成为用户的首选，硬盘逐渐向40G以上的容量发展。
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苹果 iMac G5(M9248CH/A)
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处理器类型PowerPC G5配置，主频1600MHz以上，内存容量256MB，硬盘容量80GB，显示器类型17”液晶。这是苹果电脑的创新，将主机的部件全部集成到显示器内部。显示器就是一台电脑。
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机器组成
计算机是由硬件系统（hardware system）和软件系统（software system）两部分组成的。
传统电脑系统的硬体单元一般可分为输入单元、输出单元、算术逻辑单元、控制单元及记忆单元，其中算术逻辑单元和控制单元合称中央处理单元（Center Processing Unit,CPU)。
硬件系统
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电源
电源是电脑中不可缺少的供电设备，它的作用是将220V交流电转换为电脑中使用的5V、12V、3.3V直流电，其性能的好坏，直接影响到其他设备工作的稳定性，进而会影响整机的稳定性。手提电脑在自带锂电池情况下，为手提电脑提供有效电源。
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主板
主板是电脑中各个部件工作的一个平台，它把电脑的各个部件紧密连接在一起，各个部件通过主板进行数据传输。也就是说，电脑中重要的“交通枢纽”都在主板上，它工作的稳定性影响着整机工作的稳定性。
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CPU
CPU即中央处理器，是一台计算机的运算核心和控制核心。其功能主要是解释计算机指令以及处理计算机软件中的数据。CPU由运算器、控制器、寄存器、高速缓存及实现它们之间联系的数据、控制及状态的总线构成。作为整个系统的核心，CPU也是整个系统最高的执行单元，因此CPU已成为决定电脑性能的核心部件，很多用户都以它为标准来判断电脑的档次。
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内存
内存又叫内部存储器或者是随机存储器（RAM），分为DDR内存和SDRAM内存，（但是SDRAM由于容量低，存储速度慢，稳定性差，已经被DDR淘汰了）内存属于电子式存储设备，它由电路板和芯片组成，特点是体积小，速度快，有电可存，无电清空，即电脑在开机状态时内存中可存储数据，关机后将自动清空其中的所有数据。 内存有DDR、DDR II、DDR III三大类，容量1-64GB。
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硬盘
硬盘属于外部存储器，机械硬盘由金属磁片制成，而磁片有记忆功能，所以储到磁片上的数据，不论在开机，还是关机，都不会丢失。硬盘容量很大，已达TB级，尺寸有3.5、2.5、1.8、1.0英寸等，接口有IDE、SATA、SCSI等，SATA最普遍。移动硬盘是以硬盘为存储介质，强调便携性的存储产品。市场上绝大多数的移动硬盘都是以标准硬盘为基础的，而只有很少部分的是以微型硬盘（1.8英寸硬盘等）为基础，但价格因素决定着主流移动硬盘还是以标准笔记本硬盘为基础。因为采用硬盘为存储介质，因此移动硬盘在数据的读写模式与标准IDE硬盘是相同的。移动硬盘多采用USB、IEEE1394等传输速度较快的接口，可以较高的速度与系统进行数据传输。固态硬盘用固态电子存储芯片阵列而制成的硬盘，由控制单元和存储单元（FLASH芯片）组成。固态硬盘在产品外形和尺寸上也完全与普通硬盘一致但是固态硬盘比机械硬盘速度更快。
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声卡
声卡是组成多媒体电脑必不可少的一个硬件设备，其作用是当发出播放命令后，声卡将电脑中的声音数字信号转换成模拟信号送到音箱上发出声音。
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显卡
显卡在工作时与显示器配合输出图形、文字，作用是将计算机系统所需要的显示信息进行转换驱动，并向显示器提供行扫描信号，控制显示器的正确显示，是连接显示器和个人电脑主板的重要元件，是“人机对话”的重要设备之一。
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网卡
网卡是工作在数据链路层的网路组件，是局域网中连接计算机和传输介质的接口，不仅能实现与局域网传输介质之间的物理连接和电信号匹配，还涉及帧的发送与接收、帧的封装与拆封、介质访问控制、数据的编码与解码以及数据缓存的功能等。网卡的作用是充当电脑与网线之间的桥梁，它是用来建立局域网并连接到Internet的重要设备之一。
在整合型主板中常把声卡、显卡、网卡部分或全部集成在主板上。
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调制解调器
英文名为“Modem”，俗称“猫”，即调制解调器，类型
调制解调器
有内置式和外置式，有线式和无线式。调制解调器是通过电话线上网时必不可少的设备之一。它的作用是将电脑上处理的数字信号转换成电话线传输的模拟信号。随着ADSL宽带网的普及，内置式调制解调器逐渐退出了市场。
调制解调器
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光驱
光驱
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显示器
英文名为“monitor”，显示器有大有小，有薄有厚，品种多样，其作用是把电脑处理完的结果显示出来。它是一个输出设备，是电脑必不可缺少的部件之一。分为CRT、LCD、LED三大类，接口有VGA、DVI两类。
键盘
英文名为“Keyboard”，分为有线和无线，键盘是主要的人工学输入设备，通常为104或105键，用于把文字、数字等输到电脑上，以及电脑操控。
常见计算机键盘
鼠标
英文名为“Mouse”，当人们移动鼠标时，电脑屏幕上就会有一个箭头指针跟着移动，并可以很准确指到想指的位置，快速地在屏幕上定位，它是人们使用电脑不可缺少的部件之一。 键盘鼠标接口有PS/2和USB两种。硬件的鼠标分为光电和机械两种（机械已被光电淘汰）。
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音箱
音响
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打印机
打印机
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视频设备
如摄像头、扫描仪、数码相机、数码摄像机、电视卡等设备，用于处理视频信号。
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闪存盘
英文名为“Flash disk”，闪存盘通常也被称作优盘，U盘，闪盘，是一个通用串行总线USB接口的无需物理驱动器的微型高容量移动存储产品，它采用的存储介质为闪存存储介质（Flash Memory）。闪存盘一般包括闪存（Flash Memory）、控制芯片和外壳。闪存盘具有可多次擦写、速度快而且防磁、防震、防潮的优点。闪盘采用流行的USB接口，体积只有大拇指大小，重量约20克，不用驱动器，无需外接电源，即插即用，不同电脑之间进行文件交流，存储容量从1～128GB不等，满足不同的需求。
移动存储卡及读卡器
存储卡是利用闪存（Flash Memory）技术达到存储电子信息的存储器，一般应用在数码相机、掌上电脑、MP3、MP4等小型数码产品中作为存储介质，所以样子小巧，犹如一张卡片，所以称之为闪存卡。根据不同的生产厂商和不同的应用，闪存卡有Smart Media（SM卡）、Compact Flash（CF卡），Multi Media Card（MMC卡），Secure Digital（SD卡）、Memory Stick（记忆棒），TF卡等多种类型，这些闪存卡虽然外观、规格不同，但是技术原理都是相同的。由于闪存卡本身并不能直接被电脑辨认，读卡器就是一个两者的沟通桥梁。读卡器Card Reader）可使用很多种存储卡，如Compact Flash or Smart Media or Microdrive存储卡等，作为存储卡的信息存取装置。读卡器使用USB1.1/USB2.0的传输介面，支持热拔插。与普通USB设备一样，只需插入电脑的USB端口，然后插用存储卡就可以使用了。 按照速度来划分有USB1.1、USB2.0以及USB3.0，按用途来划分，有单一读卡器和多合一读卡器。
软件系统
所谓软件是指为方便使用计算机和提高使用效率而组织的程序以及用于开发、使用和维护的有关文档。软件系统可分为系统软件和应用软件两大类。
1、系统软件
系统软件System software,由一组控制计算机系统并管理其资源的程序组成，其主要功能包括：启动计算机，存储、加载和执行应用程序，对文件进行排序、检索，将程序语言翻译成机器语言等。实际上，系统软件可以看作用户与计算机的接口，它为应用软件和用户提供了控制、访问硬件的手段，这些功能主要由操作系统完成。此外，编译系统和各种工具软件也属此类，它们从另一方面辅助用户使用计算机。下面分别介绍它们的功能。
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1）操作系统（Operating System，OS）
操作系统是管理、控制和监督计算机软、硬件资源协调运行的程序系统，由一系列具有不同控制和管理功能的程序组成，它是直接运行在计算机硬件上的、最基本的系统软件，是系统软件的核心。操作系统是计算机发展中的产物，它的主
要目的有两个：一是方便用户使用计算机，是用户和计算机的接口。比如用户键入一条简单的命令就能自动完成复杂的功能，这就是操作系统帮助的结果；二是统一管理计算机系统的全部资源，合理组织计算机工作流程，以便充分、合理地
发挥计算机的效率。操作系统通常应包括下列五大功能模块：
（1）处理器管理：当多个程序同时运行时，解决处理器（CPU）时间的分配问题。
（2）作业管理：完成某个独立任务的程序及其所需的数据组成一个作业。作业管理的任务主要是为用户提供一个使用计算机的界面使其方便地运行自己的作业，并对所有进入系统的作业进行调度和控制，尽可能高效地利用整个系统的
资源。
（3）存储器管理：为各个程序及其使用的数据分配存储空间，并保证它们互不干扰。
（4）设备管理：根据用户提出使用设备的请求进行设备分配，同时还能随时接收设备的请求（称为中断），如要求输入信息。
（5）文件管理：主要负责文件的存储、检索、共享和保护，为用户提供文件操作的方便。
操作系统的种类繁多，依其功能和特性分为分批处理操作系统、分时操作系统和实时操作系统等；依同时管理用户数的多少分为单用户操作系统和多用户操作系统；适合管理计算机网络环境的网络操作系统。
微机操作系统随着微机硬件技术的发展而发展，从简单到复杂。Microsoft公司开发的DOS是一单用户单任务系统，而Windows操作系统则是一多户多任务系统，经过十几年的发展，已从Windows 3.1发展Windows NT、Windows 2000、Windows XP、Windows vista、Windows 7和Windows 8等等。它是当前微机中广泛使用的操作系统之一。Linux是一个源码公开的操作系统，程序员可以根据自己的兴趣和灵感对其进行改变，这让Linux吸收了无数程序员的精华，不断壮大，已被越来越多的用户所采用，是Windows操作系统强有力的竞争对手。
2）语言处理系统（翻译程序）
人和计算机交流信息使用的语言称为计算机语言或称程序设计语言。计算机语言通常分为机器语言、汇编语言和高级语言三类。如果要在计算机上运行高级语言程序就必须配备程序语言翻译程序（下简称翻译程序）。翻译程序本身是一组程
序，不同的高级语言都有相应的翻译程序。翻译的方法有两种：
一种称为“解释”。早期的BASIC源程序的执行都采用这种方式。它调用机器配备的BASIC“解释程序”，在运行BASIC源程序时，逐条把BASIC的源程序语句进行解释和执行，它不保留目标程序代码，即不产生可执行文件。这种方式速度较慢，每
次运行都要经过“解释”，边解释边执行。
另一种称为“编译”，它调用相应语言的编译程序，把源程序变成目标程序（以.OBJ为扩展名），然后再用连接程序，把目标程序与库文件相连接形成可执行文件。尽管编译的过程复杂一些，但它形成的可执行文件（以.exe为扩展名）可以反复
执行，速度较快。运行程序时只要键入可执行程序的文件名，再按Enter键即可。
Program source code interpretation and compilation tasks are called compiler and interpreter. Such as FORTRAN, COBOL, PASCAL, and C and other high-level language compiler need for appropriate use; BASIC, LISP and other high-level language, required when using the appropriate interpreter.
3) Service program
Service program to provide some common service functions that provide convenience for users to develop and use computer programs, diagnostic procedures like on the PC frequently used, debugger, editor fall into this category.
4) Database Management System
Database is a collection of links according to the data stored in a certain, for a variety of applications can be shared. DBMS (Data Base Management System, DBMS) is a software system capable of processing and managing the database. Its main function is to establish, eliminate, maintaining databases and database data to perform various operations. Database system consists of a database (DB), a database management system (DBMS) and the corresponding application components. Database system not only capable of storing large amounts of data quickly is more important, the data is automatically retrieved, modified, statistics, sorting, merging and other operations, to obtain the desired information. This is a traditional file cabinet can not be done.
Database technology is the fastest growing computer technology, the most widely used branch. It can be said that in the future most of the computer application development is inseparable from the database. Therefore, understanding the database technology that is still in the computer database application environment is essential.
2, application software
In order to solve practical problems and all kinds of programs designed system called application software. From the perspective of clients, it can be divided into two types of general-purpose software and proprietary software.