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Programmers and programming languages




Computer programmers write computer programs that become the components of a computer software product. The finished software product is then distributed by the programmers or by software publishers – companies that specialize in marketing and selling software. Today most businesses and organizations purchase commercial software to avoid the time and expense of writing their own.

Most software provides a task-related environment, which includes a screen display, a means of collecting commands and data from the user, the specifications for processing data, and a method for displaying or outputting data. To create a software environment, a programmer must define properties for each element in the environment, such as where the objects appear, its shape, color and behavior.

A programming language provides the tools a programmer uses to create software and produce a lengthy list of instructions, called source code, which defines the software environment in every detail – what it looks like, how the user enters commands, and how it manipulates data. Most programmers today prefer to use a high-level language, such as C++, Java, Ada, COBOL, or Visual Basic. These languages have some similarities to human languages and produce programs that are fairly easy to test and modify.

A computer’s microprocessor understands only machine language – the instruction set that is “hard wired” within the microprocessor’s circuits. Therefore, instructions written in a high-level language must be translated into machine language before a computer can use them. The process of translating instructions can be accomplished by two special types of programs: compilers and interpreters. A compiler translates all the instructions in a program as a single batch, and the resulting machine language instructions, called object code, are placed in a new file. Most of the program files on a distribution CD for commercial software are compiled so that they contain machine language instructions that are ready for the processor to execute. As an alternative to a compiler, an interpreter converts one instruction at a time while the program is running. An interpreter reads the first instruction, converts it into machine language, and then sends it to the microprocessor. After the instruction is executed, the interpreter converts the next instruction, and so on.

Software is categorized as application software or system software. The primary purpose of application software is to help people carry out tasks using a computer. In contrast, the primary purpose of system software – your computer’s operating system, device drivers, programming languages, and utilities – is to help the computer to carry out its basic operating functions.

Software can be classified into categories (see fig. 3):

 


Fig. 3: Software categories

Comprehension check. Mark the following statements as True or False.

 

1. Computer software typically consists of many files that contain user-executable programs, support programs and data files.

2. The main executable file provides the primary set of instructions for the computer to execute and calls various support programs and data files as needed.

3. Support programs often have file extensions such as.txt,.bmp, and.hlp.

4. Individuals often write software for their personal computers.

5. High-level languages are fairly easy to test and modify.

6. A compiler converts high-level instructions into a new file containing machine language instructions.

Vocabulary practice

1. In the text find the synonyms to the given words.

start a program objective define method decrease provide perform

 

2. Fill in the blanks choosing from the variants given.

1. The instructions that tell a computer how to … a task are referred to as a computer program.

a) require b) create c) carry out d) define

2. A programming language … tools for creating a lengthy list of instructions called source code.

a) prefer b) refer to c) avoid d) provide

3. As a program is running an interpreter converts one instruction… into machine language.

a) at a time b) at the same time c) all the time

4. eVidpro.exe is a compiled program, so its instructions are immediately … by the processor.

a) provided b) modified c) executed d) adapted

5. Software includes menus, buttons, and other control objects that are … by a programmer, who designates their properties.

a) converted b) defined c) reduced d) purchased

6. The software that provides the computer with … for each use is called application software.

a) approaches b) efficiency c) utilities d) instructions

 

3. Make two-word expressions by combining words from two lists: A and B. Then fill in the gaps in the following sentences.

A: executable B: language

application code

machine file

source extensions

file software

high-level instructions

 

1. When using a Windows PC, you can start an … by clicking its icon, selecting it from a Start menu, or entering its name in the Run dialog box.

2. Computer software can be divided into two major categories: … software and system software.

3. The data files supplied with a software package sport … such as.txt,.bmp,.hlp.

4. A programming language provides tools for creating a lengthy list of instructions called ….

5. A simple instruction to add two numbers becomes a long series of 0s and 1s in a….

6. A compiler converts … into a file containing machine language instructions.

4. Fill in the gaps in the text.

Software consists of computer ___ (programs/utilities) and data files that work together to provide a computer with the ___ (instructions/approaches) and ___ (data/tools) necessary for carrying out a specific type of task, such as document production, video editing, graphic design, or Web browsing.

To create a software ___ (efficiency/environment), a programmer must define the ___ (approaches/properties) for each element in the environment, such as where an object appears, its shape, its color, and its behavior. Most programmers today prefer to use ___ (high-level/machine) languages. A computer’s microprocessor understands only ___ (machine/high-level) language, however, so a program that is written in a high-level language must be ___ (avoided/compiled) or interpreted before it can be ___ (processed/modified).

 

Speaking. Discuss the following questions.

1. What is software?

2. What kinds of files are included in a typical software product?

3. Why does software require so many files?

4. How does a programmer “write” software?

5. How does a computer process a program?

6. How is software categorized?

 

Text B

Reading. Read the text and try to guess the meaning of the words in bold. Check your variants in the dictionary.

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