Can You Work in an It Field by Only Knowing C++?

Why Programming?
You may already have used software, perchance for word processing or spreadsheets, to solve problems. Mayhap at present you lot are curious to learn how programmers write software. A program is a set of step-by-step instructions that directs the computer to do the tasks yous want it to do and produce the results you want.

There are at least 3 good reasons for learning programming:

• Programming helps you understand computers. The computer is only a tool. If you learn how to write simple programs, you will gain more than knowledge about how a figurer works.
• Writing a few unproblematic programs increases your confidence level. Many people observe neat personal satisfaction in creating a set of instructions that solve a trouble.
• Learning programming lets you lot find out quickly whether you like programming and whether you lot have the analytical plough of mind programmers need. Even if y'all decide that programming is not for yous, understanding the process certainly will increment your appreciation of what programmers and computers tin do.

A ready of rules that provides a fashion of telling a computer what operations to perform is called a programming linguistic communication. In that location is not, however, just one programming language; there are many. In this chapter yous will learn about controlling a computer through the procedure of programming. You may even discover that you might want to become a programmer.

An important betoken before we proceed: You lot volition not exist a programmer when you lot cease reading this affiliate or fifty-fifty when you finish reading the final chapter. Programming proficiency takes practice and grooming beyond the scope of this book. However, you will become acquainted with how programmers develop solutions to a diverseness of problems.

What Programmers Practise
In general, the developer'due south chore is to convert problem solutions into instructions for the computer. That is, the programmer prepares the instructions of a reckoner program and runs those instructions on the computer, tests the program to see if it is working properly, and makes corrections to the program. The developer also writes a report on the program. These activities are all washed for the purpose of helping a user fill up a need, such as paying employees, billing customers, or admitting students to higher.

The programming activities just described could exist done, perchance, as solo activities, but a programmer typically interacts with a multifariousness of people. For example, if a program is part of a system of several programs, the programmer coordinates with other programmers to make certain that the programs fit together well. If you were a programmer, you might besides accept coordination meetings with users, managers, systems analysts, and with peers who evaluate your work-simply as you evaluate theirs.

Let us turn to the programming process.

The Programming Process
Developing a program involves steps similar to any problem-solving job. In that location are five main ingredients in the programming process:

1. Defining the problem
2. Planning the solution
3. Coding the program
4. Testing the program
5. Documenting the programme

Allow us discuss each of these in turn.

1. Defining the Trouble
   Suppose that, as a programmer, you are contacted because your services are needed. You meet with users from the client system to analyze the problem, or you run across with a systems analyst who outlines the project. Specifically, the task of defining the problem consists of identifying what information technology is y'all know (input-given information), and what it is yous desire to obtain (output-the result). Eventually, you produce a written agreement that, among other things, specifies the kind of input, processing, and output required. This is non a simple process.
2. Planning the Solution
   

   Effigy 1: Flow Chart Symbols and Catamenia Chart For Mailing Letter of the alphabet

   Two common ways of planning the solution to a problem are to draw a flowchart and to write pseudocode, or possibly both. Essentially, a flowchart is a pictorial representation of a stride-by-step solution to a problem. It consists of arrows representing the management the program takes and boxes and other symbols representing actions. It is a map of what your programme is going to do and how it is going to do it. The American National Standards Institute (ANSI) has adult a standard set of flowchart symbols. Figure ane shows the symbols and how they might be used in a simple flowchart of a mutual everyday act-preparing a letter for mailing.

   Pseudocode is an English-like nonstandard linguistic communication that lets you state your solution with more than precision than you lot tin can in plain English language but with less precision than is required when using a formal programming language. Pseudocode permits you to focus on the program logic without having to be concerned but nonetheless almost the precise syntax of a particular programming linguistic communication. All the same, pseudocode is not executable on the estimator. We volition illustrate these later in this chapter, when we focus on language examples.

3. Coding the Programme
   As the programmer, your next step is to lawmaking the programme-that is, to express your solution in a programming language. You will translate the logic from the flowchart or pseudocode-or some other tool-to a programming linguistic communication. Every bit we have already noted, a programming language is a set up of rules that provides a way of instructing the estimator what operations to perform. In that location are many programming languages: Bones, COBOL, Pascal, FORTRAN, and C are some examples. You may find yourself working with ane or more of these. We volition discuss the different types of languages in detail later in this chapter.

   Although programming languages operate grammatically, somewhat like the English language, they are much more than precise. To get your program to work, you lot have to follow exactly the rules-the syntax-of the linguistic communication you are using. Of form, using the linguistic communication correctly is no guarantee that your programme will work, any more than speaking grammatically right English ways y'all know what you are talking about. The point is that correct use of the language is the required first footstep. Then your coded plan must be keyed, probably using a final or personal figurer, in a form the computer can sympathise.

   One more note here: Programmers normally employ a text editor, which is somewhat similar a word processing programme, to create a file that contains the programme. However, as a beginner, you will probably desire to write your programme code on paper kickoff.

4. Testing the Plan
   Some experts insist that a well-designed program tin can be written correctly the offset fourth dimension. In fact, they assert that there are mathematical ways to prove that a program is correct. Still, the imperfections of the globe are all the same with us, so about programmers get used to the thought that their newly written programs probably have a few errors. This is a flake discouraging at first, since programmers tend to exist precise, conscientious, detail-oriented people who have pride in their piece of work. Still, at that place are many opportunities to introduce mistakes into programs, and y'all, merely as those who have gone before you, will probably find several of them.

   Somewhen, later on coding the program, y'all must prepare to test it on the computer. This step involves these phases:

   • Desk-bound-checking. This phase, similar to proofreading, is sometimes avoided by the programmer who is looking for a shortcut and is eager to run the plan on the figurer one time it is written. Notwithstanding, with careful desk-checking you may discover several errors and possibly save yourself time in the long run. In desk-checking you lot only sit down and mentally trace, or check, the logic of the plan to attempt to ensure that it is error-gratuitous and workable. Many organizations take this stage a step further with a walkthrough, a process in which a group of programmers-your peers-review your program and offer suggestions in a collegial way.
   • Translating. A translator is a program that (1) checks the syntax of your program to brand sure the programming language was used correctly, giving you all the syntax-mistake messages, called diagnostics, and (2) then translates your program into a form the computer can understand. A past-production of the process is that the translator tells you if you have improperly used the programming linguistic communication in some manner. These types of mistakes are called syntax errors. The translator produces descriptive fault messages. For instance, if in FORTRAN you mistakenly write N=2 *(I+J))-which has two closing parentheses instead of i-y'all will get a message that says, "UNMATCHED PARENTHESES." (Dissimilar translators may provide different wording for error messages.) Programs are most usually translated by a compiler. A compiler translates your entire program at in one case. The translation involves your original program, called a source module, which is transformed by a compiler into an object module. Prewritten programs from a system library may exist added during the link/load phase, which results in a load module. The load module can and so be executed past the computer.
   • Debugging. A term used extensively in programming, debugging means detecting, locating, and correcting bugs (mistakes), usually by running the program. These bugs are logic errors, such as telling a figurer to repeat an operation simply not telling it how to stop repeating. In this phase yous run the program using test data that you devise. You lot must plan the test data advisedly to make certain you lot test every part of the plan.
5. Documenting the Program
   Documenting is an ongoing, necessary process, although, as many programmers are, you may be eager to pursue more than heady reckoner-centered activities. Documentation is a written detailed description of the programming bicycle and specific facts virtually the program. Typical program documentation materials include the origin and nature of the problem, a brief narrative description of the program, logic tools such as flowcharts and pseudocode, information-tape descriptions, program listings, and testing results. Comments in the program itself are as well considered an essential office of documentation. Many programmers document every bit they code. In a broader sense, program documentation tin be role of the documentation for an unabridged organisation.

   The wise programmer continues to certificate the program throughout its design, development, and testing. Documentation is needed to supplement human retentivity and to aid organize program planning. Also, documentation is critical to communicate with others who take an involvement in the program, especially other programmers who may be office of a programming team. And, since turnover is loftier in the figurer industry, written documentation is needed so that those who come after y'all can make whatever necessary modifications in the program or track down whatsoever errors that you missed.

Programming every bit a Career
There is a shortage of qualified personnel in the figurer field. Before y'all join their ranks, consider the advantages of the computer field and what information technology takes to succeed in it.

The Joys of the Field
Although many people make career changes into the figurer field, few choose to get out it. In fact, surveys of computer professionals, especially programmers, consistently report a loftier level of job satisfaction. In that location are several reasons for this contentment. One is the challenge-most jobs in the computer industry are not routine. Some other is security, since established calculator professionals can unremarkably observe piece of work. And that work pays well-y'all will probably not exist rich, just you should exist comfortable. The computer industry has historically been a rewarding identify for women and minorities. And, finally, the industry holds endless fascination since it is always changing.

What It Takes
You need, of course, some credentials, most often a two- or four-year degree in computer information systems or informatics. The requirements and salaries vary by the organization and the region, so we will not dwell on these here. Beyond that, the person most likely to land a task and move upward the career ladder is the one with excellent communication skills, both oral and written . These are besides the qualities that can be observed by potential employers in an interview. Promotions are sometimes tied to advanced degrees (an M.B.A. or an M.Due south. in computer science).

Open up Doors
The overall outlook for the computer field is promising. The Bureau of Labor Statistics shows, through the year 2010, a 72 percent increment in programmers and a 69 percent increase in system use today, and we will discuss the most popular ones later In the chapter. Earlier we turn to specific languages, however, we demand to discuss levels of language.

Levels of Language
Programming languages are said to be "lower" or "higher," depending on how shut they are to the linguistic communication the computer itself uses (Os and 1s = depression) or to the language people use (more than English language-like-high). Nosotros will consider 5 levels of linguistic communication. They are numbered 1 through five to correspond to levels, or generations. In terms of ease of utilise and capabilities, each generation is an improvement over its predecessors. The five generations of languages are

1. Automobile language
2. Assembly languages
3. Loftier-level languages
4. Very loftier-level languages
5. Natural languages

Let us look at each of these categories.

Machine Linguistic communication
Humans practise not like to bargain in numbers solitary-they prefer messages and words. But, strictly speaking, numbers are what machine linguistic communication is. This lowest level of language, motorcar language, represents data and program instructions as 1s and Os-binary digits respective to the on and off electrical states in the computer. Each type of computer has its own machine linguistic communication. In the early days of computing, programmers had rudimentary systems for combining numbers to represent instructions such as add and compare. Primitive by today's standards, the programs were not convenient for people to read and utilise. The figurer manufacture quickly moved to develop assembly languages.

Assembly Languages

Figure 2: Example Assembly Language Program

Today, assembly languages are considered very low level-that is, they are non as convenient for people to use as more recent languages. At the time they were developed, nonetheless, they were considered a great leap forward. To replace the Is and Os used in machine language, associates languages utilize mnemonic codes, abbreviations that are easy to think: A for Add, C for Compare, MP for Multiply, STO for storing information in retention, and and then on. Although these codes are not English words, they are still- from the standpoint of human being convenience-preferable to numbers (Os and 1s) alone. Furthermore, associates languages let the utilise of names- perhaps RATE or TOTAL-for memory locations instead of actual address numbers. only similar machine language, each type of computer has its own assembly language.

The developer who uses an assembly language requires a translator to convert the assembly language program into machine language. A translator is needed because machine language is the simply language the computer can actually execute. The translator is an assembler program, too referred to every bit an assembler. It takes the programs written in associates language and turns them into automobile linguistic communication. Programmers need not worry about the translating aspect; they need but write programs in assembly language. The translation is taken care of by the assembler.

Although assembly languages stand for a pace forward, they still accept many disadvantages. A key disadvantage is that assembly language is detailed in the extreme, making assembly programming repetitive, wearisome, and fault decumbent. This drawback is apparent in the plan in Effigy 2. Assembly language may be easier to read than machine language, but it is still tedious.

Loftier-Level Languages
The first widespread use of high-level languages in the early 1960s transformed programming into something quite different from what it had been. Programs were written in an English-like mode, thus making them more convenient to employ. As a result, a developer could reach more with less try, and programs could now direct much more circuitous tasks.

These so-called tertiary-generation languages spurred the great increase in data processing that characterized the 1960s and 1970s. During that time the number of mainframes in use increased from hundreds to tens of thousands. The impact of 3rd-generation languages on our order has been enormous.

Of course, a translator is needed to translate the symbolic statements of a high-level language into computer-executable auto language; this translator is usually a compiler. There are many compilers for each language and 1 for each type of reckoner. Since the machine language generated by one figurer's COBOL compiler, for instance, is non the auto linguistic communication of another figurer, information technology is necessary to have a COBOL compiler for each type of computer on which COBOL programs are to exist run. Keep in mind, withal, that even though a given program would be compiled to different machine language versions on different machines, the source program itself-the COBOL version-can be essentially identical on each machine.

Some languages are created to serve a specific purpose, such as controlling industrial robots or creating graphics. Many languages, however, are extraordinarily flexible and are considered to be general-purpose. In the past the majority of programming applications were written in BASIC, FORTRAN, or COBOL-all full general-purpose languages. In add-on to these three, another popular high-level language is C, which we will discuss later on.

Very High-Level Languages
Languages chosen very high-level languages are oftentimes known by their generation number, that is, they are called fourth-generation languages or, more just, 4GLs.

Definition
Volition the real fourth-generation languages please stand up upward? At that place is no consensus most what constitutes a fourth-generation language. The 4GLs are essentially autograph programming languages. An performance that requires hundreds of lines in a third-generation linguistic communication such as COBOL typically requires merely v to 10 lines in a 4GL. However, beyond the basic criterion of conciseness, 4GLs are difficult to draw.

Characteristics
Fourth-generation languages share some characteristics. The first is that they make a true break with the prior generation-they are basically not-procedural. A procedural language tells the reckoner how a job is done: Add this, compare that, do this if something is truthful, and then along-a very specific stride-by-step procedure. The first 3 generations of languages are all procedural. In a nonprocedural linguistic communication, the concept changes. Here, users define but what they want the computer to practise; the user does not provide the details of just how it is to be washed. Obviously, it is a lot easier and faster just to say what you lot desire rather than how to get information technology. This leads us to the issue of productivity, a key characteristic of fourth-generation languages.

Productivity
Folklore has it that fourth-generation languages tin can amend productivity by a factor of five to 50. The sociology is true. About experts say the average comeback gene is about 10-that is, you can exist ten times more productive in a fourth-generation language than in a third-generation language. Consider this request: Produce a written report showing the total units sold for each product, by customer, in each month and year, and with a subtotal for each customer. In addition, each new customer must outset on a new folio. A 4GL request looks something similar this:

            Table FILE SALES 	SUM UNITS Past Calendar month BY Customer BY Product 	ON CUSTOMER SUBTOTAL Folio Pause 	END          

Even though some training is required to do fifty-fifty this much, you tin can see that it is pretty simple. The third-generation linguistic communication COBOL, however, typically requires over 500 statements to fulfill the same request. If we define productivity as producing equivalent results in less time, then fourth-generation languages conspicuously increase productivity.

Downside
Fourth-generation languages are not all peaches and cream and productivity. The 4GLs are still evolving, and that which is withal evolving cannot be fully defined or standardized. What is more than, since many 4GLs are easy to use, they attract a large number of new users, who may then overcrowd the computer organisation. Ane of the main criticisms is that the new languages lack the necessary command and flexibility when it comes to planning how you lot desire the output to expect. A common perception of 4GLs is that they exercise not make efficient use of car resources; however, the benefits of getting a program finished more than quickly can far outweigh the extra costs of running it.

Benefits
Fourth-generation languages are beneficial because

• They are results-oriented; they emphasize what instead of how.
• They improve productivity considering programs are easy to write and alter.
• They can be used with a minimum of training past both programmers and nonprogrammers.
• They shield users from needing an awareness of hardware and program structure.

It was not long ago that few people believed that 4GLs would ever be able to supplant tertiary-generation languages. These 4GL languages are beingness used, but in a very limited manner.

Query Languages
A variation on 4th-generation languages are query languages, which tin can be used to retrieve information from databases. Information is usually added to databases according to a plan, and planned reports may too be produced. But what about a user who needs an unscheduled report or a report that differs somehow from the standard reports? A user tin can learn a query language fairly hands and so be able to input a asking and receive the resulting report right on his or her own terminal or personal computer. A standardized query language, which can be used with several different commercial database programs, is Structured Query Language, popularly known equally SQL. Other popular query languages are Query-past-Case, known as QBE, and Intellect.

Natural Languages
The discussion "natural" has become about equally pop in calculating circles as it has in the supermarket. Fifth-generation languages are, equally you may gauge, even more than sick-defined than fourth-generation languages. They are almost often called natural languages because of their resemblance to the "natural" spoken English language language. And, to the director new to computers for whom these languages are now aimed, natural means homo-like. Instead of being forced to key right commands and data names in correct order, a manager tells the estimator what to do by keying in his or her own words.

Figure 3: Example of Natural language Interaction

A manager can say the same thing any number of ways. For case, "Get me tennis racket sales for Jan" works just as well as "I desire January tennis racket revenues." Such a request may contain misspelled words, lack articles and verbs, and even utilise slang. The natural language translates man instructions-bad grammar, slang, and all-into code the computer understands. If it is not sure what the user has in mind, information technology politely asks for further explanation.

Natural languages are sometimes referred to as knowledge-based languages, because natural languages are used to collaborate with a base of noesis on some subject. The utilize of a natural language to access a knowledge base is called a cognition-based system.

Consider this request that could exist given in the 4GL Focus: "SUM ORDERS BY Date BY REGION." If we change the request and, still in Focus, say something like "Give me the dates and the regions subsequently you've added upwardly the orders," the reckoner volition spit dorsum the convenient version of "Y'all've got to be kidding" and give up. Merely some natural languages can handle such a asking. Users can relax the structure of their requests and increment the freedom of their interaction with the information.

Here is a typical natural language request:

            Report THE BASE Salary, COMMISSIONS AND YEARS OF 	SERVICE BROKEN DOWN Past STATE AND City FOR SALESCLERKS 	IN NEW Bailiwick of jersey AND MASSACHUSETTS.          

Y'all can hardly get closer to conversational English than that.

An case of a natural language is shown in Effigy 3. Natural languages excel at easy data access. Indeed, the about common awarding for natural languages is interacting with databases.

Choosing a Language
How do you choose the language with which to write your program?
At that place are several possibilities:

• In a work environs, your director may decree that anybody on your project will use a certain language.
• You may use a sure language, particularly in a business surroundings, based on the demand to interface with other programs; if 2 programs are to work together, it is easiest if they are written in the same language.
• You may choose a language based on its suitability for the task. For example, a business program that handles large files may be all-time written in the business language COBOL.
• If a program is to be run on unlike computers, information technology must exist written in a language that is portable-suitable on each type of calculator-so that the plan need be written simply in one case.
• You may be limited by the availability of the linguistic communication. Not all languages are available in all installations or on all computers.
• The language may be limited to the expertise of the developer; that is, the programme may have to be written in a language the available developer knows.
• Mayhap the simplest reason, 1 that applies to many amateur programmers, is that they know the language called BASIC considering it came with-or was inexpensively purchased with-their personal computers.

Major Programming Languages

Figure 4: Flow Nautical chart For Averaging Numbers

The following sections on individual languages will give y'all an overview of the 3rd-generation languages in mutual use today: FORTRAN (a scientific language), COBOL (a business language), Bones (simple language used for instruction and business organisation), Pascal (pedagogy), Ada (military machine), and C (general purposed).

This chapter will present programs written in some of these languages. You will too come across output produced past each program. Each plan is designed to detect the boilerplate of three numbers; the resulting boilerplate is shown in the sample output matching each program. Since all programs perform the same task, you lot will see some of the differences and similarities among the languages. We do non await you to sympathise these programs; they are here simply to let yous glimpse each language. Effigy 4 presents the flowchart and pseudocode for the task of averaging numbers. As nosotros discuss each language, we will provide a program for averaging numbers that follows the logic shown in this figure.

FORTRAN: The First High-Level Language

Figure 5: Case Fortran Programme To Average Numbers

Developed by IBM and introduced in 1954, FORTRAN-for FORmula TRANslator-was the showtime high-level linguistic communication. FORTRAN is a scientifically oriented language-in the early on days use of the computer was primarily associated with engineering science, mathematical, and scientific research tasks.

FORTRAN is noted for its brevity, and this feature is part of the reason why it remains popular. This language is very expert at serving its master purpose, which is execution of circuitous formulas such as those used in economic analysis and engineering. Although in the past it was considered express in regard to file processing or data processing, its capabilities accept been greatly improved.

Not all programs are organized in the same way. Organisation varies according to the language used. In many languages (such as COBOL), programs are divided into a series of parts. FORTRAN programs are not equanimous of unlike parts (although it is possible to link FORTRAN programs together); a FORTRAN programme consists of statements i later the other. Different types of data are identified every bit the information is used. Descriptions for data records appear in format statements that accompany the READ and WRITE statements. Effigy 5 shows a FORTRAN program and a sample output from the program.

COBOL: The Linguistic communication of Business organisation

Figure vi: Example COBOL Program to Average Numbers

In the 1950s FORTRAN had been developed, but there was still no accepted high-level programming language appropriate for business. The U.S. Department of Defense force in detail was interested in creating such a standardized language, and so it chosen together representatives from government and diverse industries, including the computer industry. These representatives formed CODASYL-COnference of Information System Languages. In 1959 CODASYL introduced COBOL-for COmmon BusinessOriented Language.

The U.South. authorities offered encouragement past insisting that anyone attempting to win government contracts for computer-related projects had to utilize COBOL. The American National Standards Plant first standardized COBOL in 1968 and, in 1974, issued standards for another version known every bit ANSI-COBOL. Afterwards more than 7 controversial years of manufacture contend, the standard known every bit COBOL 85 was approved, making COBOL a more usable modern-twenty-four hours software tool. The main benefit of standardization is that COBOL is relatively machine independent- that is, a program written for one type of reckoner can exist run with only slight modifications on another type for which a COBOL compiler has been developed.

COBOL is very good for processing large files and performing relatively simple business calculations, such as payroll or interest. A noteworthy characteristic of COBOL is that information technology is English-like-far more than so than FORTRAN or BASIC. The variable names are set up in such a fashion that, even if you know naught nigh programming, you can all the same understand what the program does. For example:

            IF SALES-AMOUNT IS GREATER THAN SALES-QUOTA 		COMPUTE COMMISSION = MAX-Charge per unit * SALES-Corporeality 	ELSE 		COMPUTE COMMISSION = MIN-Charge per unit * SALES-AMOUNT.          

Once you lot understand programming principles, it is not too hard to add together COBOL to your repertoire. COBOL can exist used for just well-nigh whatever chore related to business organisation programming; indeed, it is especially suited to processing alphanumeric data such as street addresses, purchased items, and dollar amounts-the data of business. However, the feature that makes COBOL then useful-its English language-like appearance and easy readability-is also a weakness considering a COBOL plan can be incredibly verbose. A developer seldom knocks out a quick COBOL plan. In fact, there is hardly such a thing equally a quick COBOL program; there are just too many program lines to write, even to accomplish a unproblematic task. For speed and simplicity, Bones, FORTRAN, and Pascal are probably better bets.

As you can see in Effigy half-dozen, a COBOL program is divided into four parts called divisions. The identification division identifies the program by name and often contains helpful comments equally well. The surround division describes the computer on which the program will be compiled and executed. It also relates each file of the program to the specific physical device, such equally the tape bulldoze or printer, that will read or write the file. The data division contains details nearly the data candy by the programme, such as type of characters (whether numeric or alphanumeric), number of characters, and placement of decimal points. The procedure division contains the statements that give the computer specific instructions to deport out the logic of the program.

It has been stylish for some time to criticize COBOL: Information technology is quondam-fashioned, cumbersome, and inelegant. In fact, some companies, devoted to fast, nimble program development, are converting to the more trendy language C. But COBOL, with more than 30 years of staying power, is notwithstanding famous for its clear code, which is easy to read and debug.

BASIC: For Beginners and Others

Figure 7: Case Basic Program to Average Numbers

Bones-Beginners' All-purpose Symbolic Pedagogy Lawmaking-is a common linguistic communication that is like shooting fish in a barrel to learn. Adult at Dartmouth College, Basic was introduced by John Kemeny and Thomas Kurtz in 1965 and was originally intended for utilize by students in an academic environment. In the tardily 1960s it became widely used in interactive time-sharing environments in universities and colleges. The use of BASIC has extended to business and personal computer systems.

The master characteristic of Bones is one that may exist of interest to many readers of this book: Basic is easy to learn, even for a person who has never programmed before. Thus, the language is used often to train students in the classroom. Basic is too used by non-programming people, such as engineers, who observe it useful in trouble solving. For many years, BASIC was looked down on by "existent programmers," who complained that it had also many limitations and was not suitable for circuitous tasks. Newer versions, such equally Microsoft's QuickBASIC, include substantial improvements. An instance of a Basic programme and its output are shown in Figure 7.

Pascal: The Language of Simplicity
Named for Blaise Pascal, the seventeenth-century French mathematician, Pascal was developed as a teaching language past a Swiss computer scientist, Niklaus Wirth, and commencement became available in 1971. Since that time information technology has become quite popular, get-go in Europe and now in the United States, particularly in universities and colleges offering computer science programs.

The foremost feature of Pascal is that it is simpler than other languages -it has fewer features and is less wordy than virtually. In add-on to the popularity of Pascal in college computer science departments, the language has likewise made large inroads in the personal figurer market equally a simple yet sophisticated alternative to Basic. Over the years new versions have improved on the original capabilities of Pascal. Today, Borland'southward Turbo Pascal leads the Pascal world because its designers eliminated well-nigh of the drawbacks of the original Pascal. Turbo Pascal is used by the business community and is often the choice of nonprofessional programmers who need to write their own programs.

Ada: Named for the Countess
Is any software worth over $25 billion? Not any more, co-ordinate to Defence Department experts. In 1974 the U.S. Department of Defense had spent that corporeality on all kinds of software for a hodgepodge of languages for its needs. The reply to this problem turned out to exist a new language chosen Ada-named for Countess Ada Lovelace, "the first programmer" (see Appendix B). Sponsored by the Pentagon, Ada was originally intended to be a standard language for weapons systems, but information technology has also been used successfully for commercial applications. Introduced in 1980, Ada has the support non only of the defense establishment only also of such industry heavyweights every bit IBM and Intel, and Ada is even available for some personal computers. Although some experts take said Ada is too complex, others say that it is easy to learn and that information technology will increase productivity. Indeed, some experts believe that it is by far a superior commercial language to such standbys as COBOL and FORTRAN.

Widespread employ of Ada is considered unlikely by many experts. Although at that place are many reasons for this (the military services, for instance, take different levels of enthusiasm for information technology), probably its size- which may hinder its use on personal computers-and complication are the greatest barriers. Although the Department of Defense is a market place in itself, Ada has not caught on to the extent that Pascal and C have, especially in the business community.

C, C++, Java, and Javascript
A language invented by Dennis Ritchie at Bell Labs in 1972, C produces code that approaches assembly language in efficiency while still offering high-level linguistic communication features. C was originally designed to write systems software only is now considered a general-purpose language. C contains some of the best features from other languages, including Pascal. C compilers are simple and compact. A key attraction is that information technology is independent of the architecture of whatever particular machine, a fact that contributes to the portability of C programs. That is, a C program can exist run on more than i blazon of computer afterward it has been compiled for that automobile.

Although C is simple and elegant, it is not uncomplicated to learn. Information technology was adult for gifted programmers, and the learning bend may be steep. Straightforward tasks may exist solved easily in C, merely complex problems require mastery of the language.

An interesting side notation is that the availability of C on personal computers has greatly enhanced the value of personal computers for budding software entrepreneurs. A cottage software industry can use the same basic tool-the language C-used by established software companies such every bit Microsoft and Borland. Today C is has been replaced past its enhanced cousin, C++. C++ in plow is beingness challenged by web-aware languages similar Java and Javascript, that wait and human activity a lot like C++, but add features to support working with networked computers, among other things.

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Source: https://homepage.cs.uri.edu/faculty/wolfe/book/Readings/Reading13.htm

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