The Major Computer Operations Include

Why Programming?
You lot may already have used software, perhaps for discussion processing or spreadsheets, to solve problems. Perchance at present you lot are curious to learn how programmers write software. A programme is a set of step-by-step instructions that directs the computer to do the tasks y'all want it to do and produce the results you desire.

There are at least 3 good reasons for learning programming:

• Programming helps yous empathize computers. The estimator is just a tool. If you larn how to write simple programs, y'all will gain more cognition near how a computer works.
• Writing a few simple programs increases your confidence level. Many people find great personal satisfaction in creating a prepare of instructions that solve a problem.
• Learning programming lets y'all find out rapidly whether you similar programming and whether you accept the belittling plow of mind programmers need. Fifty-fifty if you lot decide that programming is not for y'all, understanding the process certainly will increment your appreciation of what programmers and computers can exercise.

A set of rules that provides a way of telling a computer what operations to perform is called a programming language. In that location is non, yet, but ane programming language; in that location are many. In this chapter you volition learn about decision-making a computer through the procedure of programming. You lot may fifty-fifty discover that you might want to get a programmer.

An of import indicate before we go along: Y'all will not be a programmer when you finish reading this affiliate or even when yous finish reading the final chapter. Programming proficiency takes practice and training beyond the scope of this book. Withal, you will become acquainted with how programmers develop solutions to a multifariousness of issues.

What Programmers Do
In general, the developer'south job is to catechumen problem solutions into instructions for the estimator. That is, the programmer prepares the instructions of a computer program and runs those instructions on the reckoner, tests the program to see if it is working properly, and makes corrections to the plan. The developer too writes a report on the program. These activities are all done for the purpose of helping a user fill up a demand, such as paying employees, billing customers, or admitting students to college.

The programming activities only described could be done, perhaps, as solo activities, simply a developer typically interacts with a variety of people. For instance, if a program is function of a organisation of several programs, the programmer coordinates with other programmers to brand sure that the programs fit together well. If y'all were a programmer, you might likewise have coordination meetings with users, managers, systems analysts, and with peers who evaluate your piece of work-merely equally 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 procedure:

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

Permit the states discuss each of these in plow.

1. Defining the Problem
   Suppose that, equally a programmer, you lot are contacted because your services are needed. Yous meet with users from the customer organization to analyze the problem, or you meet with a systems analyst who outlines the project. Specifically, the task of defining the trouble consists of identifying what it is y'all know (input-given data), and what it is you want to obtain (output-the result). Eventually, you produce a written understanding that, amidst other things, specifies the kind of input, processing, and output required. This is non a simple process.
2. Planning the Solution
   

   Figure 1: Menses Nautical chart Symbols and Flow Chart For Mailing Alphabetic character

   Two mutual ways of planning the solution to a trouble are to draw a flowchart and to write pseudocode, or maybe both. Essentially, a flowchart is a pictorial representation of a pace-past-step solution to a trouble. Information technology consists of arrows representing the direction the program takes and boxes and other symbols representing actions. It is a map of what your plan is going to exercise and how it is going to practise it. The American National Standards Institute (ANSI) has developed a standard gear up of flowchart symbols. Figure 1 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-similar nonstandard language that lets you state your solution with more than precision than y'all can in obviously English language but with less precision than is required when using a formal programming language. Pseudocode permits you lot to focus on the program logic without having to exist concerned just yet virtually the precise syntax of a particular programming language. However, pseudocode is not executable on the computer. We will illustrate these later in this chapter, when we focus on language examples.

3. Coding the Program
   Equally the developer, your adjacent step is to lawmaking the program-that is, to express your solution in a programming linguistic communication. You lot volition interpret the logic from the flowchart or pseudocode-or some other tool-to a programming language. As we have already noted, a programming language is a set of rules that provides a way of instructing the calculator what operations to perform. There are many programming languages: BASIC, COBOL, Pascal, FORTRAN, and C are some examples. You lot may find yourself working with one or more of these. Nosotros will talk over 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 precise. To get your program to work, you lot have to follow exactly the rules-the syntax-of the language you are using. Of course, using the language correctly is no guarantee that your program volition work, any more than speaking grammatically correct English means you know what yous are talking nigh. The point is that correct use of the language is the required first step. Then your coded program must be keyed, probably using a terminal or personal figurer, in a form the computer tin understand.

   1 more than annotation here: Programmers normally use a text editor, which is somewhat like a give-and-take processing program, to create a file that contains the program. Yet, equally a beginner, you will probably want to write your programme code on paper first.

4. Testing the Program
   Some experts insist that a well-designed program can exist written correctly the start time. In fact, they assert that there are mathematical ways to prove that a programme is right. However, the imperfections of the globe are still with us, so about programmers get used to the thought that their newly written programs probably have a few errors. This is a bit discouraging at first, since programmers tend to be precise, conscientious, detail-oriented people who accept pride in their piece of work. Still, at that place are many opportunities to introduce mistakes into programs, and you lot, but equally those who have gone before you, will probably find several of them.

   Somewhen, after coding the program, you must prepare to examination information technology on the computer. This footstep involves these phases:

   • Desk-checking. This phase, similar to proofreading, is sometimes avoided by the programmer who is looking for a shortcut and is eager to run the program on the calculator once it is written. Yet, with careful desk-bound-checking yous may detect several errors and peradventure save yourself time in the long run. In desk-bound-checking you lot but sit downwards and mentally trace, or check, the logic of the program to effort to ensure that information technology is error-free and workable. Many organizations take this phase 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 manner.
   • Translating. A translator is a program that (one) checks the syntax of your program to make sure the programming language was used correctly, giving you lot all the syntax-error letters, called diagnostics, and (ii) then translates your programme into a form the computer tin understand. A past-product of the process is that the translator tells you if yous have improperly used the programming language in some way. These types of mistakes are chosen syntax errors. The translator produces descriptive fault messages. For instance, if in FORTRAN you lot mistakenly write Due north=2 *(I+J))-which has ii endmost parentheses instead of one-you will get a message that says, "UNMATCHED PARENTHESES." (Different translators may provide different wording for fault messages.) Programs are most normally translated by a compiler. A compiler translates your entire program at one fourth dimension. The translation involves your original program, chosen 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 then be executed by the calculator.
   • 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 every bit telling a estimator to repeat an functioning but not telling it how to end repeating. In this phase you run the program using test data that y'all devise. Y'all must plan the test data carefully to make sure y'all examination every part of the plan.
5. Documenting the Plan
   Documenting is an ongoing, necessary procedure, although, equally many programmers are, you lot may exist eager to pursue more heady calculator-centered activities. Documentation is a written detailed description of the programming cycle and specific facts about the program. Typical plan documentation materials include the origin and nature of the problem, a brief narrative description of the program, logic tools such as flowcharts and pseudocode, data-record descriptions, program listings, and testing results. Comments in the program itself are also considered an essential part of documentation. Many programmers document as they code. In a broader sense, program documentation can exist part of the documentation for an unabridged system.

   The wise programmer continues to document the program throughout its blueprint, evolution, and testing. Documentation is needed to supplement human memory and to assist organize plan planning. Also, documentation is critical to communicate with others who take an interest in the program, especially other programmers who may exist office of a programming team. And, since turnover is high in the computer industry, written documentation is needed so that those who come after you lot tin can make whatsoever necessary modifications in the program or track down any errors that you missed.

Programming as a Career
At that place is a shortage of qualified personnel in the computer field. Earlier 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 brand career changes into the computer field, few choose to leave information technology. In fact, surveys of computer professionals, especially programmers, consistently report a high level of task satisfaction. There are several reasons for this contentment. 1 is the challenge-most jobs in the computer industry are non routine. Another is security, since established computer professionals can ordinarily find piece of work. And that work pays well-yous will probably not be rich, but you should exist comfortable. The computer industry has historically been a rewarding place for women and minorities. And, finally, the industry holds endless fascination since it is always changing.

What It Takes
Yous need, of form, 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 state a job and move up the career ladder is the one with excellent communication skills, both oral and written . These are also the qualities that tin can be observed past 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 increase in programmers and a 69 percent increase in system use today, and nosotros will discuss the most pop ones later In the chapter. Before we turn to specific languages, yet, we need to discuss levels of linguistic communication.

Levels of Language
Programming languages are said to be "lower" or "higher," depending on how close they are to the language the figurer itself uses (Bone and 1s = low) or to the linguistic communication people utilize (more English-similar-high). We volition consider five levels of language. They are numbered ane through 5 to correspond to levels, or generations. In terms of ease of use and capabilities, each generation is an improvement over its predecessors. The five generations of languages are

1. Machine language
2. Assembly languages
3. Loftier-level languages
4. Very high-level languages
5. Natural languages

Let us look at each of these categories.

Machine Language
Humans do not like to deal in numbers solitary-they prefer letters and words. But, strictly speaking, numbers are what auto linguistic communication is. This lowest level of language, machine language, represents data and program instructions as 1s and Os-binary digits corresponding to the on and off electric states in the calculator. Each type of computer has its ain automobile linguistic communication. In the early days of computing, programmers had rudimentary systems for combining numbers to stand for instructions such as add and compare. Primitive past today's standards, the programs were not convenient for people to read and apply. The reckoner industry quickly moved to develop assembly languages.

Associates Languages

Figure 2: Example Assembly Language Program

Today, assembly languages are considered very low level-that is, they are not every bit convenient for people to employ as more recent languages. At the time they were developed, however, they were considered a great jump forward. To replace the Is and Os used in machine language, assembly languages use mnemonic codes, abbreviations that are easy to remember: A for Add, C for Compare, MP for Multiply, STO for storing information in memory, so on. Although these codes are non English words, they are still- from the standpoint of human being convenience-preferable to numbers (Os and 1s) lonely. Furthermore, assembly languages permit the use of names- perhaps RATE or Total-for retentiveness locations instead of bodily address numbers. simply similar machine language, each type of figurer has its own associates language.

The programmer who uses an associates linguistic communication requires a translator to convert the associates language program into machine language. A translator is needed because car linguistic communication is the only linguistic communication the computer tin really execute. The translator is an assembler programme, also referred to as an assembler. It takes the programs written in assembly language and turns them into motorcar language. Programmers need not worry nigh the translating aspect; they demand only write programs in assembly language. The translation is taken care of past the assembler.

Although associates languages represent a step forrad, they still accept many disadvantages. A primal disadvantage is that assembly language is detailed in the extreme, making assembly programming repetitive, dull, and error prone. This drawback is credible in the program in Figure two. Assembly language may be easier to read than machine language, but it is nonetheless tedious.

High-Level Languages
The first widespread use of loftier-level languages in the early 1960s transformed programming into something quite different from what it had been. Programs were written in an English-like manner, thus making them more convenient to use. Equally a result, a programmer could achieve more with less try, and programs could at present direct much more than complex tasks.

These and then-called 3rd-generation languages spurred the great increase in data processing that characterized the 1960s and 1970s. During that fourth dimension the number of mainframes in employ increased from hundreds to tens of thousands. The impact of third-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 machine language; this translator is ordinarily a compiler. There are many compilers for each language and one for each type of figurer. Since the automobile language generated by ane estimator'southward COBOL compiler, for instance, is non the car language of some other reckoner, it is necessary to take a COBOL compiler for each type of computer on which COBOL programs are to be run. Continue in mind, however, that fifty-fifty though a given program would be compiled to different machine linguistic communication versions on different machines, the source program itself-the COBOL version-tin can be essentially identical on each car.

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

Very High-Level Languages
Languages called very high-level languages are often known by their generation number, that is, they are called quaternary-generation languages or, more merely, 4GLs.

Definition
Will the real fourth-generation languages please stand up? There is no consensus about what constitutes a fourth-generation language. The 4GLs are essentially shorthand programming languages. An operation that requires hundreds of lines in a 3rd-generation language such as COBOL typically requires but five to ten lines in a 4GL. However, beyond the basic criterion of conciseness, 4GLs are difficult to describe.

Characteristics
Fourth-generation languages share some characteristics. The outset is that they make a true break with the prior generation-they are basically non-procedural. A procedural language tells the reckoner how a task is washed: Add together this, compare that, do this if something is truthful, and and so along-a very specific step-by-step process. The first 3 generations of languages are all procedural. In a nonprocedural language, the concept changes. Here, users define only what they want the calculator to do; the user does not provide the details of just how it is to be done. Obviously, it is a lot easier and faster just to say what you want rather than how to get information technology. This leads us to the effect of productivity, a key characteristic of quaternary-generation languages.

Productivity
Folklore has information technology that fourth-generation languages can better productivity by a gene of 5 to 50. The folklore is true. About experts say the average improvement gene is about 10-that is, yous can be 10 times more productive in a quaternary-generation language than in a third-generation language. Consider this request: Produce a report showing the full units sold for each product, by client, in each month and yr, and with a subtotal for each client. In addition, each new customer must outset on a new folio. A 4GL asking looks something like this:

            TABLE FILE SALES 	SUM UNITS BY MONTH BY CUSTOMER BY Production 	ON Customer SUBTOTAL Folio Suspension 	END          

Fifty-fifty though some training is required to do even this much, you can encounter that it is pretty elementary. The third-generation linguistic communication COBOL, all the same, typically requires over 500 statements to fulfill the same asking. If we define productivity as producing equivalent results in less time, then fourth-generation languages clearly increase productivity.

Downside
Quaternary-generation languages are not all peaches and cream and productivity. The 4GLs are still evolving, and that which is still evolving cannot be fully defined or standardized. What is more, since many 4GLs are like shooting fish in a barrel to use, they attract a big number of new users, who may then overcrowd the computer organisation. One of the main criticisms is that the new languages lack the necessary command and flexibility when it comes to planning how you lot want the output to look. A common perception of 4GLs is that they practise not brand efficient use of machine 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 grooming past both programmers and nonprogrammers.
• They shield users from needing an awareness of hardware and plan structure.

It was not long ago that few people believed that 4GLs would e'er exist able to replace tertiary-generation languages. These 4GL languages are existence used, simply in a very express style.

Query Languages
A variation on quaternary-generation languages are query languages, which tin exist used to remember data from databases. Data is usually added to databases according to a plan, and planned reports may also 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 learn a query language fairly hands and and then be able to input a request and receive the resulting report right on his or her own terminal or personal computer. A standardized query language, which can exist used with several unlike commercial database programs, is Structured Query Language, popularly known as SQL. Other popular query languages are Query-by-Example, known as QBE, and Intellect.

Natural Languages
The word "natural" has get almost every bit popular in computing circles as information technology has in the supermarket. 5th-generation languages are, as you may guess, even more ill-divers than 4th-generation languages. They are nigh often called natural languages considering of their resemblance to the "natural" spoken English language. And, to the managing director new to computers for whom these languages are now aimed, natural means human-like. Instead of existence forced to key correct commands and data names in correct order, a manager tells the figurer 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 example, "Get me tennis racket sales for Jan" works merely also as "I desire January tennis noise revenues." Such a request may contain misspelled words, lack articles and verbs, and even use slang. The natural language translates human instructions-bad grammar, slang, and all-into code the computer understands. If it is not sure what the user has in mind, it 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 knowledge on some field of study. The use of a tongue to access a knowledge base is called a knowledge-based system.

Consider this request that could be given in the 4GL Focus: "SUM ORDERS BY DATE BY REGION." If nosotros modify the request and, still in Focus, say something like "Requite me the dates and the regions later on you've added upwards the orders," the computer volition spit back the user-friendly version of "You lot've got to be kidding" and give up. Only some natural languages tin handle such a request. Users can relax the construction of their requests and increase the freedom of their interaction with the data.

Here is a typical natural language request:

            REPORT THE Base of operations SALARY, COMMISSIONS AND YEARS OF 	SERVICE Cleaved Downwardly By STATE AND Metropolis FOR SALESCLERKS 	IN NEW Bailiwick of jersey AND MASSACHUSETTS.          

You tin can inappreciably get closer to conversational English than that.

An example of a natural language is shown in Effigy three. Natural languages excel at like shooting fish in a barrel data access. Indeed, the most common application for natural languages is interacting with databases.

Choosing a Language
How do you choose the linguistic communication with which to write your plan?
There are several possibilities:

• In a work environment, your manager may decree that everyone on your projection will use a certain linguistic communication.
• You lot may utilize a sure language, specially in a business environment, based on the need to interface with other programs; if two programs are to work together, it is easiest if they are written in the same linguistic communication.
• Yous may choose a linguistic communication based on its suitability for the task. For example, a business program that handles large files may be best written in the business language COBOL.
• If a plan is to be run on unlike computers, information technology must be written in a language that is portable-suitable on each blazon of computer-and so that the plan need be written only once.
• You lot may exist limited by the availability of the language. Non all languages are available in all installations or on all computers.
• The language may be express to the expertise of the developer; that is, the program may have to exist written in a language the bachelor programmer knows.
• Perhaps the simplest reason, one that applies to many amateur programmers, is that they know the language called BASIC considering information technology came with-or was inexpensively purchased with-their personal computers.

Major Programming Languages

Figure iv: Catamenia Chart For Averaging Numbers

The following sections on individual languages will give you an overview of the third-generation languages in common utilise today: FORTRAN (a scientific language), COBOL (a business organisation language), BASIC (simple linguistic communication used for education and business), Pascal (instruction), Ada (military), and C (general purposed).

This chapter will present programs written in some of these languages. You lot will as well see output produced by each program. Each program is designed to observe the average of 3 numbers; the resulting average is shown in the sample output matching each program. Since all programs perform the same task, you will encounter some of the differences and similarities among the languages. We practice non wait yous to understand these programs; they are here just to let you glimpse each language. Figure 4 presents the flowchart and pseudocode for the task of averaging numbers. As we talk over each linguistic communication, we will provide a program for averaging numbers that follows the logic shown in this figure.

FORTRAN: The First Loftier-Level Linguistic communication

Figure 5: Example Fortran Program To Boilerplate Numbers

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

FORTRAN is noted for its brevity, and this characteristic is role of the reason why information technology remains popular. This language is very good at serving its primary purpose, which is execution of complex 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 have been greatly improved.

Not all programs are organized in the same way. System varies according to the language used. In many languages (such as COBOL), programs are divided into a serial of parts. FORTRAN programs are non composed of different parts (although it is possible to link FORTRAN programs together); a FORTRAN plan consists of statements one after the other. Unlike types of information are identified as the data is used. Descriptions for data records appear in format statements that back-trail the READ and WRITE statements. Effigy 5 shows a FORTRAN program and a sample output from the program.

COBOL: The Linguistic communication of Business

Effigy 6: Case COBOL Programme to Average Numbers

In the 1950s FORTRAN had been developed, simply in that location was still no accepted high-level programming language advisable for business. The U.S. Department of Defense in detail was interested in creating such a standardized linguistic communication, and 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.Southward. government offered encouragement by insisting that anyone attempting to win government contracts for computer-related projects had to use COBOL. The American National Standards Institute kickoff standardized COBOL in 1968 and, in 1974, issued standards for another version known as ANSI-COBOL. Afterward more than seven controversial years of industry debate, the standard known as COBOL 85 was approved, making COBOL a more than usable modern-solar day software tool. The principal benefit of standardization is that COBOL is relatively car independent- that is, a program written for one type of computer tin can be run with simply slight modifications on another type for which a COBOL compiler has been developed.

COBOL is very expert for processing large files and performing relatively unproblematic business calculations, such every bit payroll or interest. A noteworthy characteristic of COBOL is that it is English-similar-far more so than FORTRAN or BASIC. The variable names are fix in such a style that, fifty-fifty if you lot know nothing about programming, you lot can still understand what the program does. For example:

            IF SALES-Corporeality IS GREATER THAN SALES-QUOTA 		COMPUTE Committee = MAX-RATE * SALES-Corporeality 	ELSE 		COMPUTE COMMISSION = MIN-RATE * SALES-AMOUNT.          

One time you understand programming principles, it is not too hard to add COBOL to your repertoire. COBOL tin be used for just nigh any task 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. Nevertheless, the feature that makes COBOL so useful-its English-like appearance and easy readability-is likewise a weakness considering a COBOL program can be incredibly verbose. A programmer seldom knocks out a quick COBOL programme. In fact, there is inappreciably such a thing every bit a quick COBOL program; there are just too many program lines to write, even to accomplish a elementary task. For speed and simplicity, Basic, FORTRAN, and Pascal are probably better bets.

As y'all can see in Figure 6, a COBOL plan is divided into four parts called divisions. The identification division identifies the program by proper name and often contains helpful comments every bit well. The environment division describes the computer on which the plan will be compiled and executed. It likewise relates each file of the program to the specific concrete device, such every bit the tape drive or printer, that volition read or write the file. The data partition contains details about the data candy by the program, such every bit type of characters (whether numeric or alphanumeric), number of characters, and placement of decimal points. The procedure segmentation contains the statements that requite the calculator specific instructions to acquit out the logic of the plan.

Information technology has been fashionable for some fourth dimension to criticize COBOL: It is old-fashioned, cumbersome, and inelegant. In fact, some companies, devoted to fast, nimble programme development, are converting to the more than trendy linguistic communication C. Merely COBOL, with more than than xxx years of staying power, is still famous for its clear code, which is piece of cake to read and debug.

BASIC: For Beginners and Others

Figure vii: Case Bones Program to Average Numbers

BASIC-Beginners' All-purpose Symbolic Didactics Lawmaking-is a common language that is easy to learn. Developed at Dartmouth Higher, Basic was introduced past John Kemeny and Thomas Kurtz in 1965 and was originally intended for use by students in an bookish environment. In the late 1960s it became widely used in interactive time-sharing environments in universities and colleges. The utilise of Bones has extended to business and personal reckoner systems.

The primary feature of Bones is one that may be of interest to many readers of this volume: BASIC is like shooting fish in a barrel to acquire, even for a person who has never programmed before. Thus, the language is used often to train students in the classroom. Basic is also used by non-programming people, such every bit engineers, who observe it useful in problem solving. For many years, BASIC was looked downward on by "real programmers," who complained that it had besides many limitations and was not suitable for circuitous tasks. Newer versions, such equally Microsoft's QuickBASIC, include substantial improvements. An example of a BASIC program and its output are shown in Effigy 7.

Pascal: The Language of Simplicity
Named for Blaise Pascal, the seventeenth-century French mathematician, Pascal was developed as a didactics linguistic communication by a Swiss computer scientist, Niklaus Wirth, and first became bachelor in 1971. Since that time it has become quite popular, first in Europe and at present in the Usa, particularly in universities and colleges offer computer science programs.

The foremost characteristic of Pascal is that it is simpler than other languages -it has fewer features and is less wordy than most. In addition to the popularity of Pascal in college computer scientific discipline departments, the language has also made large inroads in the personal computer market every bit a simple still sophisticated culling to BASIC. Over the years new versions take improved on the original capabilities of Pascal. Today, Borland's Turbo Pascal leads the Pascal world considering its designers eliminated about of the drawbacks of the original Pascal. Turbo Pascal is used by the business community and is oft the choice of nonprofessional programmers who need to write their own programs.

Ada: Named for the Countess
Is any software worth over $25 billion? Non any more, co-ordinate to Defense Section experts. In 1974 the U.S. Department of Defence had spent that amount on all kinds of software for a hodgepodge of languages for its needs. The answer to this trouble turned out to be a new language called 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, only it has also been used successfully for commercial applications. Introduced in 1980, Ada has the support not only of the defense establishment but as well of such industry heavyweights as IBM and Intel, and Ada is even available for some personal computers. Although some experts have said Ada is too complex, others say that it is easy to larn and that it volition increase productivity. Indeed, some experts believe that it is by far a superior commercial linguistic communication to such standbys as COBOL and FORTRAN.

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

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

Although C is elementary and elegant, it is not elementary to acquire. It was adult for gifted programmers, and the learning curve may be steep. Straightforward tasks may be solved easily in C, but circuitous 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 manufacture tin utilise the same bones tool-the linguistic communication C-used by established software companies such as Microsoft and Borland. Today C is has been replaced by its enhanced cousin, C++. C++ in plow is being challenged by web-aware languages like Java and Javascript, that expect and act a lot similar C++, but add together features to support working with networked computers, amid other things.

The Major Computer Operations Include,

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

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