Programming language generations

STRUCTURE (4)

Ex.2 a) Read the sentences and analyze their structure:

1. These abbreviations are used to represent main steps or "generations" in the history of programming languages.

2. In Java the output is called bytecode.

3. 4GL is designed to be closer to natural language than a 3GL language.

4. Languages for accessing databases are often described as 4GLs.

5. Today, assembler programming is used only where very efficient control over processor operations is needed.

The Passive Voice:

Data	is	lost
Данные	потерянны
Что?	Что с данными сделано?
Подлежащее	Сказуемое
Объект над которым совершено действие	Действие, которое совершено

Note: in computer messages the auxiliary verbs are often omitted:

e.g. Data is lost = Data lost.

The basic form of the Passive Voice:

to be + Ved(VIII)

the Present Tense – am/is/are loaded, found

the Past Tense – was/were loaded, found

the Future Tense – shall/will be loaded, found

b) Pay attention to the following sentences:

1. Historically, most programs have been written in "higher-level" languages such as COBOL, FORTRAN, PL/I, and C.

2. C is a structured, procedural programming language that has been widely used both for operating systems and applications.

3. C is being quickly replaced as the programming language by C++.

4. Java can be used to create complete applications that may run on a single computer or be distributed among servers and clients in a network.

5. Using a language that comes with a virtual machine for each platform, your source language statements need to be compiled only once and will then run on any platform.

c) Change the sentences into the Passive Voice:

1. A programmer writes language statements.

2. The program processes the source code.

3. An assembler converts the assembler language statements into machine language.

4. The Central Processing Unit (CPU) of a computer executes elementary instructions.

5. Most languages share many functional features.

d) Translate into English:

1. Последовательность нулей и единиц иногда называется машинным кодом.

2. PL/I был разработан в начале 1960-х (in the early 1960s) как альтернатива ассемблеру.

3. “Виртуальная машина” используется для обозначения либо операционной системы либо любой программы, которая запускает компьютер.

4. LISP был создан для работы над проблемами искусственного интеллекта (artificial intelligence).

5. Программы на языке Ассемблера выполняются быстрее, чем программы тех же задач, написанные на других языках.

Ex.3 Read and translate into Russian:

In the computer industry, these abbreviations are used to represent main steps or "generations" in the history of programming languages.

1GL or first-generation language was (and still is) machine language or the level of instructions and data that the processor is actually given to work on (which in computers is a string of 0s and 1s).

2GL or second-generation language is assembler language. An assembler converts the assembler language statements into machine language.

3GL or third-generation language is a "high-level" programming language, such as PL/I, C, or Java.

A compiler converts the statements of a specific high-level programming language into machine language. (In the case of Java, the output is called bytecode, which is converted into appropriate machine language by a Java virtual machine that runs as part of an operating system platform.)

4GL or fourth-generation language is designed to be closer to natural language than a 3GL language. Languages for accessing databases are often described as 4 GLs.

5GL or fifth-generation language is programming that uses a visual or graphical development interface to create source language that is usually compiled with a 3 GL or 4 GL language compiler. Microsoft, Borland, IBM, and other companies make 5GL visual programming products for developing applications in Java, for example. Visual programming allows you to easily envision object-oriented programming class hierarchies and drag icons to assemble program components.

Ex.4 Retell the text “Programming language generations”.

Ex.5 Read and translate into Russian:

· An assembler is a program that takes basic computer instructions and converts them into a pattern of binary digit that the computer's processor can use to perform its basic operations.

Today, assembler programming is used only where very efficient control over processor operations is needed. Historically, most programs have been written in "higher-level" languages such as COBOL, FORTRAN, PL/I, and C. These languages are easier to learn and faster to write programs with than assembler language. The program that processes the source code written in these languages is called a compiler. Like the assembler, a compiler takes higher-level language statements and reduces them to machine code.

·
A compiler is a special program that processes statements written in a particular programming language and turns them into machine language or "code" that a computer's processor uses. Typically, a programmer writes language statements in a language such as Pascal or C one line at a time using an editor. This file contains what is called the source statements. The programmer then runs the appropriate language compiler, specifying the name of the file that contains the source statements. When executing (running), the compiler first analyzes all of the language statements syntactically one after the other and then builds the output code. Traditionally, the output of the compilation has been called object code or sometimes an object module. The object code is machine code that the processor can process or "execute" one instruction at a time.

· Bytecode is computer source code that is processed by a program. The virtual machine converts generalized machine instruction into specific machine instructions (instructions that this computer's processor will understand). Bytecode is the result of compiler source code written in any language that supports this approach (подход). Most computer languages, such as C and C++, require a separate compiler for each computer platform. Windows and the Intel line of microprocessor architectures are one platform; Apple and the PowerPC processors are another. Using a language that comes with a virtual machine for each platform, your source language statements need to be compiled only once and will then run on any platform.

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