Computer Science. The English Language Perspective - Беликова (1176925), страница 11

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This is also referred to as assemblylanguage, and is converted into 1GL. Languages of the Third Generation (3GL). Words andcommands were added to the usage of program creation.This is in addition to the numbers and symbols that werepreviously used in 1GL and 2GL. Also considered as highlevel languages, they have a syntax that is relatively easy to63understand.

Some examples of programming languages inthe third generation include Javascript, Java, C and C++.Languages of the Fourth Generation (4GL). Theselanguages are extremely close to the human language, andare generally used for database access. Among others, thislanguage consists of ColdFusion and SQL.Languages of the Fifth Generation (5GL). These languagesare most commonly used for neural networks, which areforms of artificial intelligence in an attempt to imitate theway the human mind works.There are three basic types of computer programminglanguages.

They are machine, assembly and high-level.Machine languageMachine language is the only language that a computerunderstands. Each statement in a machine language program isa sequence of bits. Each bit may be set to 0 or 1. Series of bitsrepresent instructions that a computer can understand. Forexample, the number 455 is represented by the bit sequence111000111. Machine language is a low-level programminglanguage. It is easily understood by computers but difficult toread by people. This is why people use higher levelprogramming languages.

Programs written in high-levellanguages are compiled and/or interpreted into machinelanguage so computers can execute them.Assembly languageAssembly language is a representation of machine language. Inother words, each assembly language instruction translates to amachine language instruction. The advantage of assemblylanguage is that its instructions are readable. For example,assembly language statements like MOV and ADD are morerecognizable than sequences of 0s and 1s.

Though assemblylanguage statements are readable, the statements are still lowlevel. Another disadvantage of assembly language is that it is64not portable. In other words, assembly language programs arespecific to a particular hardware. But this can be an advantagefor programmers who are targeting a specific platform andneed full control over the hardware.High-level languageHigh-level languages are what most programmers use.Languages such as C++ and Java are all high-level languages.One advantage of high-level languages is that they are easilyreadable. The statements in these languages are English-like.For example, you can gain a basic understanding of what a Javaprogram is doing by simply reading the program source code.High-level languages use English words as statements.

Loopsin Java programs are indicated by the words for, while and do.Another advantage of high-level languages is that they are lesstedious to use. A single statement in a high-level language cantranslate into many machine language statements. Finally, highlevel languages are usually portable.A disadvantage of high-level languages is that they are usuallyless powerful and less efficient. Since statements are high-level,you cannot code at the bit level the way you can with assemblylanguage. High-level languages also need to be compiledand/or interpreted into machine language before execution.Notes:Neural network – математическая или кибернетическаямодель биологической нейронной сетиMachine language – набор бинарных цифр или битов,которые компьютер считывает и воспринимаетAssembly language – промежуточный язык междумашинным кодом и языком высокого уровняHigh-level language – компьютерный язык высокогоуровня,позволяетразрабатыватьпрограммныеприложения, используя обычные слова и символы, а недвоичные числа65Assignments1.

Translate the sentences from the text into Russian inwriting paying attention to the underlined words andphrases:1. Languages of the Second Generation provide a way forprogrammers to incorporate symbolic names into thelanguage in addition to the numbers.2. Language of the Fourth Generation is extremely close tothe human language, and is generally used for databaseaccess.3. Languages of the Fifth Generation are most commonlyused for neural networks, which are forms of artificialintelligence in an attempt to imitate the way the humanmind works.4. Programs written in high-level languages are compiledand/or interpreted into machine language so computerscan execute them.5. Assembly language statements like MOV and ADD aremore recognizable than sequences of 0s and 1s.6.

You can gain a basic understanding of what a Javaprogram is doing by simply reading the program sourcecode.2. Answer the following questions:1. Why are there five generations of programminglanguages?2. What is the principal difference between low-level andhigh-level languages?3. To what extent is assembly language similar to amachine language?664. Can the programs written in high-level languages beexecuted by the computer directly?5. What are the advantages and disadvantages of highlevel languages?3.

Translate into English:Пять поколений языков программированияИногдаразличаютпятьпоколенийязыковпрограммирования, правда данное разделение являетсяспорным:Первое поколениеНачало 1950-х годов - язык первых компьютеров.Первый язык ассемблера, созданный по принципу «однаинструкция - одна строка».

Основная отличительнаяособенность: ориентирование на конкретный компьютер.Второе поколениеКонец 1950-х - начало 1960-х г.г. Разработансимвольный ассемблер, в котором появилось понятиепеременной. Это первый полноценный язык. Основнаяотличительнаяособенность:ориентированиенаабстрактный компьютер с такой же системой команд.Третье поколение1960-е г.г. - Языки программирования высокого уровня.Их характеристики:• относительная простота;• независимость от конкретного компьютера;использованиямощных• возможностьсинтаксических конструкций.Простотаязыкапозволяетписатьнебольшиепрограммыилюдям,которыенеявляютсяпрофессиональнымипрограммистами.Основнаяотличительная особенность языка третьего поколения:ориентирование на алгоритм (алгоритмические языки).67Четвертое поколениеНачало 1970-х г.г.

до сегодняшнего времени. Создаютсяязыки, предназначенные для реализации крупныхпроектов.Проблемно-ориентированныеязыки,оперирующие конкретными понятиями узкой области. Какправило, в такие языки встраивают мощные операторы,позволяющие одной строкой описывать функции, дляописаниякоторыхязыкаммладшихпоколенийпотребовалось бы сотни или даже тысячи строк исходногокода. Основная отличительная особенность языкачетвертого поколения: приближение к человеческой речи(декларативные языки).Пятое поколениеПятого поколения языков программирования пока несуществует.

По прогнозам, 5GL будет оперировать метамета-данными.Сейчас существует единственный язык, которыйработает с мета-мета-данными, - это язык командменеджеров пакетов или менеджеров зависимостей, такихкак apt, yum, smart, maven, cpan и другие. Использованиеapt-get,yumиsmartчрезвычайноповысилопроизводительностьсистемныхадминистраторовпримерно в 1000-и раз. Использование менеджеровзависимостей, таких как maven, cpan, rakudo, pim,easy_install,действительнозначительноповысилопроизводительность программистов, примерно в 10 раз. Ксожалению, эти языки являются языками команднойстроки и не являются языками программирования.4.

Give the summary of the text using the key terms.68PROGRAMMING LANGUAGE APPLICATIONSRead the following words and word combinations and usethem for understanding and translation of the text:spreadsheet – (динамическая) электронная таблица,табличная программаto embed – внедрять, встраиватьdiversity – разнообразиеto be content – быть согласнымelaborate – детально разработанныйdecimal numbers – десятичные числаrather than - ...а не...therefore – следовательноto burden – обременятьmark-up language – язык разметкиpervasive – широко распространенныйfloating-point computations – вычисления с плавающейточкойComputers have been applied to a myriad of different areas,from controlling nuclear power plants to providing videogames in mobile phones.

Because of this great diversity incomputer use, programming languages with very differentgoals have been developed. We can also understand why thereare hundreds of programming languages: two different classesof problems may demand different levels of abstraction, anddifferent programmers have different ideas on how abstractionshould be done. A C programmer is perfectly content to workat a level of abstraction that requires specification ofcomputations using arrays and indices, while an author of areport prefers to “program” using a language consisting of thefunctions of a word-processor.Virtually all successful programming languages were originallydesigned for one specific use. This is not to say that eachlanguage is good for only one purpose.69Scientific applications.

The first digital computers, whichappeared in the 1940s, were used and indeed invented forscientific applications. Typically, scientific applications havesimple data structures but require large numbers of floatingpoint arithmetic computations. The most common datastructures are arrays and matrices; the most common controlstructures are counting loops and selections.

The early highlevel programming languages invented for scientificapplications were designed to provide for those needs. Theircompetitor was assembly language, so efficiency was a primaryconcern. The first language for scientific applications wasFORTRAN.Business applications. The use of computers for businessapplications began in the 1950s. Special computers weredeveloped for this purpose, along with special language. Thefirst successful high-level language for business was COBOL,the initial version of which appeared in 1960.

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