微型計算機的硬件及軟件介紹

計算機是人類科學技術上一項偉大的成就，如今計算機的應用範圍已經從科學計算擴展到人類社會的各個領域。計算機之所以如此普及，是由其自身特點所決定的。接下來小編爲大家整理了微型計算機的硬件及軟件介紹。希望對你有幫助哦!

　　Computer Hardware

A computer is a fast and accurate symbol processing system. It can accept， store， process data and produce output results. A computer can automatically process data without human intervention. However， it must be given a set of instruction to guide it， step by step， through processes. The set of instructions is called a program， The program is stored physically inside the machine， making it a program.

All computer systems of interest to us are similar. They contain hardware components for input， central processing unit and output. The system on the small-scale is called a microcomputer or minicomputer. Continuing up the size scale， the mainframe computer is one that may offer a faster processing speed and a greater storage capacity than a typical mini. Finally comes the supercomputer， designed to process complex scientific applications， which is the largest and fastest.

Although the capacity of computers' storage locations is varied， every computer stores numbers， letters， and other characters in a coded form. Every character in the storage is represented by a string of 0s and 1s， the only digits founded in the binary numbering system. BCD and ASCII are popular computer codes.

　　Memory

Primary memory is known as random access memory (RAM) and simple named memory. It is the storage area within the computer that holds programs and data during processing. Memory is only temporary storage area; when processing is complete， memory is cleared. The user needs to load or enter data and programs into the computer memory when using any application on the computer.

Different computers have different amounts of memory space， referred to as memory size， ranging from 4， 8 megabytes to 64megabytes. Today， the memories of some microcomputers even can be expandable to hundreds of megabytes.

　　CPU

CPU is the abbreviation of Central Processing Unit， which is the heart of a computer like the head of a family. Once the power of a computer is turned on， all the behaviors are under the control of CPU. CPU is in an iron box together with other devices such as disk drives， a main memory and a switching power supply etc. In Chinese， the iron box is conventionally called the mainframe. On the back of the mainframe box， there are various ports， with which CPU may be linked with input and output devices.

　　Computer software

Most people think of software as all of the amazing application programs available today for microcomputers. But there are other forms of computer software that make it possible to use application programs. Software is the collective name for all the programs and instructions that direct a computer's operations. Generally software can be divided into three types： system software， application software and support software， system software monitors and controls the system's hardware. Application software performs specific tasks for the user. Support software is a series of software， which support development and maintenance of other software. Software is created through the use of programming languages.

　　The computer Language

The role of a program is to deliver user's intention to a computer and direct it to work. That is to say， a program is a dialogue tool for interacting between a man and a computer， as well as a bridge to transmit information. In general， the characters， phases and their syntax rules for programming are generally called “programming language”。

Programming languages are divided into three types： machine language， which is also called an instruction system， is the only one used directly by computers. The assembler language is a kind of symbolic language. It adopted some mnemonic symbols which can show the instructional functions to present the content of the program. The high-level language is a programming language based on English. Its operators and expressions are similar to ordinary mathematical formulas. General users can easily master a high-level language and make programs in it.

　　Programming

Programming is， at its simplest， the way people tell computers what to do， when to do it， and how to do it. A program is a specific set of instructions written by one or more people， which direct the action of a computer system. It may be a very simple or complicated set of instructions. It may be written by a beginning computer user or by a top computer expert. It may be written in simple English or in a language spoken only by computers. Just as writing a fiction， programming is a process of creating art.

　　What is Object Oriented Programming?

Object oriented programming (OOP) is a new way of approaching the job of programming that differs from traditional programming because it uses objects as data structures to enhance productivity， simplify programming， get reusability and improve software reliability. All object oriented programming languages have three characteristics in common： objects， polymorphism and inheritance. Let's take a look at these concepts.

Object is a data structure that contains both structured information and related operations. An object can contain other objects. In this way， the object is given both data properties and behaviors， and so object oriented programs can better reflect the real world they are trying to simulate. Polymorphism essentially means that one name can be used for several related but slightly different purposes. Inheritance is the process by which one object can acquire the properties of another object. This is important because it supports the concept of classification. For example， a red delicious apple is a part of the classification apple， which in turn is a part of the fruit class， which is under the larger class food.

　　計算機的硬件

計算機是一種快速、精確的符號加工系統，它能接收、存儲、處理數據併產生輸出結果。計算機可以在不需要人工干預的情況下自動處理數據，然而必須給它一組指令去引導它，使之逐步地通過一個個處理過程，這組指令稱之爲程序。

我們目前所使用的計算機，其硬件成分都是相似的，它們的硬件設備均包含輸入設備，中央處理器和出設備。小規模的系統叫做微型計算機或小型計算機。隨着規模的增加，形成了大型計算機，它比一般的小型計算機有更快的處理速度和更大的存儲容量。最後是超型計算機，它用於處理更復雜的科學問題，這種計算機規模最大、速度最快。

儘管計算機存儲單元的存儲能力不同，但是每一個計算機都以編碼的形式存儲數字、字母和其它的字符。每一個存儲的字符都被表示成0或1組成的串，0和1是二進制編碼系統中僅有的數字。BCD碼和ASCII碼都是流行的計算機代碼。

附註：BCD (Binary-Coded Decimal)：二進制編碼的十進制

附註：ASCII(American National Standard Code for Information Interchange)：美國國家信息交換標準代碼

　　內存

主存儲器又稱爲隨機存取存儲器，簡稱內存。它是計算機在處理過程中存儲程序和數據的區域。內存只是一個臨時的存儲區域，處理完成後內存就被清空了。用戶在使用應用程序需將數據和程序調入計算機內存。

不同的計算機具有不同的內存空間，內存空間是指內存的大小，從4兆、8兆到32兆不等。目前有些微機的內存甚至可以擴充到上百兆。

　　中央處理單元

CPU是中央處理單元的英文縮寫。它是計算機的心臟，好比一家之主一樣。計算機一旦通電運行，則所有的行爲都要在它的控制之下運行。CPU同其它設備如磁盤驅動器、內存和開關穩壓電源等被裝在一個鐵箱子中。 在中文裏，這個箱子被習慣地稱爲主機。在主機箱的背後， 有各種端口，用來溝通CPU 和其它輸入輸出設備的聯繫。

　　計算機軟件

很多人認爲軟件就是目前微機上使用的所有令人驚奇的應用程序。但是還有一些其它形式的用以支持應用程序運行的計算機軟件。 軟件是所有指揮計算機操作的指令和程序的統稱。 通常軟件被劃分成三類： 系統軟件、 應用軟件和支撐軟件。 系統軟件負責監視和控制計算機硬件;應用軟件爲用戶完成具體的任務; 支撐軟件是支撐其它軟件的開發與維護的一系列軟件。軟件都是使用程序設計語言創造出來的。

　　計算機語言

程序的作用就是向計算機轉達用戶的意圖，指揮計算機工作， 也就是說，程序是人機對話的工具，是人與電腦交流信息的橋樑。 通常，程序設計所使用的符號、短語及其語法規則通稱爲程序設計語言。

程序設計語言分爲機器語言、彙編語言和高級語言三類。機器語言是計算機唯一能直接使用的語言，也叫做計算機指令系統;彙編語言是一種符號語言，它採用一些能反映指令功能的助記符表達程序的內容;高級語言是一種以英文爲基礎的設計語言， 其中的運算符和表達式都和通常的數學公式類似。 一般用戶也能很容易地掌握一種高級語言， 並可以用它來編制程序。

　　程序設計

程序設計，簡單地說， 就是人們告訴計算機做什麼，什麼時候做以及怎樣做的方式。 一個程序就是一組指令的集合，由一個或多人編寫，用於指導計算機系統的動作。這個指令的集合可能非常簡單，也可能十分複雜。它可能是一個初學計算機的用戶編寫的也有可能是由高級計算機專家編寫的。 它可以用簡單的英語編寫，也可以用只有計算機“說”的語言編寫。如同寫小說一樣，程序設計也是一個藝術創造的過程。

　　何爲面向對象的程序設計

與傳統的編程方法不同， 面向對象的程序設計(OOP)是一種新的編程方法，它使用對象作爲其數據結構以提高生產率，簡化程序設計，獲得可複用性和提高軟件的可靠性。所有的面向對象的程序設計語言都具有對象、多態和繼承的特點。 讓我們來看一下這幾個概念。

對象是一種數據結構。 它既含有結構化的信息又含有相關的操作。一個對象可以含有另外一個對象。通過這種方式，對象被賦予數據特徵和行爲，因此，使用面向對象程序能夠更好地反映程序欲模擬的現實世界。多態本質上就是使用一個名字來描述幾個相關但又有所區別的目的。繼承就是一個對象獲得另一個對象的特徵的過程。這一點非常重要，因爲它支持分類的概念。例如，一個美味可口的紅蘋果是蘋果類的一員，而蘋果又是水果類的一部分，再進一步，水果又是食物這更高一級類的一部分。