If builders built buildings the way the programmers wrote programs, the first woodpecker to come along would destroy civilization.

In the beginning, computers used numbers as the primary form of input data. Later with the development of hardware and software the definition of data was expanded. Now users can input not only numerical but also textual (letters and special characters), audiovisual (music, video, voice, pictures), and physical (light, sound, temperature, pressure) data.

Although a modern computer is capable of accepting many types of input, it can only operate on digitally formatted data, just as original computers did. Hence software must be created to interface the computer with the various types of input data. Because a computer runs on electricity, data must be stored as a series of on and off patterns.

Computer circuits can be in only one of two states: either on (represented by 1) or off (represented by 0). Each numeric value is known as a binary digit (bit) and unique combinations of those two bits, are what binary code, or machine language, is called. Different patterns in binary code could then be used to represent various input characters. Once data has been converted to binary form, computers would then apply a software program (applications or apps) to the digital input data, sequentially execute the instructions, and successfully process it into information.

Engineers quickly realized that writing in binary code (machine language) was extremely difficult and time consuming. Writing software programs in numerical (or digital) format was an immense task for anyone. Therefore, it was necessary to develop software into a more user-friendly format.

As programmers developed existing code, new computer capabilities were noticed and the demand for even more advanced software increased. It inspired programmers to develop more software.

The early days of computing were restricted to scientific and engineering applications, but after the once-imagined possibilities became realities, the general public’s appetite for computer accessibility and capability began to skyrocket. Thousands of new programs were being written as swiftly as possible and yet the demand continued to increase. Of the thousands of programs available, software types typically fall into 2 categories: system software and application software.

System software controls various internal computer activities. Any software that controls such activities will fall into one of three categories: programming language, operating system, and utility software.

Programming languages are the various methods of writing computer instructions. The instructions adhere to a particular set of protocols for each language. Through the years, more than 200 languages have been developed, some of which are quite specialized. Some of the most popular languages include BASIC, COBOL, Pascal, C, C++, Visual Basic, and FORTRAN. But regardless of which language a program was written in, a computer can only process binary code. Therefore, each language must eventually be converted back to binary code before any instructions can be followed.

The first generation of computer languages was machine language. Machine language was difficult to use It was time consuming and filled with errors.

The second generation of computer language, assembly language, was developed in the 1950s and reduced the complexity of program-authoring by using symbols instead of 0’s and 1’s. However, each computer or family of computers had its own assembly language which prevented the software of one computer model from being used on a different computer model. Although programming became easier to write, it remained idiosyncratic with its lack of portability.

Third generation languages, called high-level languages, were developed for two reasons: one- so programmers could work on different computers without having to learn a new assembly language each time, and software written on one computer could be used on another. A compiler (program translator) was used to help solve these problems by translating a program into machine language and checking the program for syntax errors (spelling or grammar mistakes unique to a specific language). The advent of the compiler greatly reduced the programmer’s burden of memorizing specific code for each machine.

Fourth generation languages, called very high-level languages, use a similar language translator (called interpreters) but require fewer lines of code because they rely on objects of code that are reusable. These predefined objects have numerous strengths such as portability, easy structuring, and simplified development but also make the languages less flexible.

Until 1970, IBM bundled its software with its computers, selling the hardware along with the software needed to run it. In 1970, IBM began charging a separate fee for its software, thus opening a market for independent software developers to write programs that would run on IBM machines. By the time the first personal computer (PC), called the Altair, hit the market in the 1975, there were many well-developed computer languages and competent programmers available to write software for the new industry. Micro Instrumentation and Telemetry Systems, Inc., the manufacturers of the Altair, introduced an operating system that was a version of Beginner’s All-Purpose Symbolic Instruction Code (BASIC), written by Bill Gates and Paul Allen, and enabled Altair owners to write their own programs.

The operating system (OS) is a group of system programs that help in the operation of a computer by telling the computer how to interpret commands, process the inputs and outputs, and manage data. The OS is automatically loaded when the PC is started and can activate other programs.

By far the most common OS for PC’s is the Disk Operating System (DOS). Windows 98, Me, NT, 2000 etc and AT&T’s UNIX are other examples of popular operating systems.

Operating systems have become larger and more sophisticated in response to the capabilities of new hardware and other software. But in the early 1980s, just before IBM introduced its first PC, the dominant OS was the Control Program for Microprocessors (CP / M), developed by Gary Kildall in 1973 for Intel Corporation . In 1974, Kildall founded Digital Research, Inc. and sold CP / M by mail order. CP / M was the first OS that would run on PCs made by different manufacturers, and it had the largest number of programs for data and word processing and calculations. But IBM chose DOS as its operating system, and when its open-architecture PC hit the market, programmers jumped at the chance to write application software for it. Although it was a powerful operating system, in 1983 CP / M was on only four percent of the PCs and few software developers supported it, preferring to write for the growing DOS-based market.

Utility software expands the performance of the operating system by adding functions that are not part of the original OS. Utilities perform troubleshooting jobs, inspecting diskettes for damage, file conversion, defragmenting, data compression, and file spooling. Some utility programs, such as Symantec’s Norton Utilities, even retrieve data from damaged disks. Utilities can also be used to customize the OS environment.

Application software (apps) is used to perform specialized functions or specific jobs. Specific jobs might be to create a family tree, learn basic math or quantum physics, create a plot for a novel, do payroll and accounting, draw flowcharts etc. Regardless of type of task, users can choose from thousands of apps to facilitate the job. To help sort out the thousands of apps, the software publishing industry tracks more than 35 categories. Four of the major categories that represent the progress of application software, made since the late 1970s, are: spreadsheet, database management, word processing and entertainment.

The first successful spreadsheet program was VisiCalc, written for the Apple II. Introduced by Dan Bricklin and Bob Frankston in 1979, VisiCalc gave PC users the ability to prepare detailed budgets and financial analyses. Its popularity soared because it enabled PC users to do something that a mainframe could not – enter numerical or financial data and immediately see its affect on other numbers. At a time when the PC was struggling to be taken seriously, VisiCalc changed its perception from a toy to a legitimate business tool.

Following the success of VisiCalc, in 1982 Lotus 1-2-3 was introduced and quickly became the number one spreadsheet software. One reason for its success was that it integrated three applications: spreadsheet, graph generation, and database management. Many other spreadsheet programs followed, including Microsoft Excel (1987), and Wind Z for the Apple Mac (1988).

Database Management. One of the applications that initially seemed to be limited to mainframes and minicomputers was the management of large databases. When Ashton-Tate introduced dBase II for CP / M, it was the first serious database manager for PCs. Developed as a program called Vulcan by Wayne Ratliff to manage a company football pool, dBase went on to be a powerful business tool for DOS machines. Like Lotus 1-2-3, dBase II was also an integrated software, combining database management, spreadsheet, graph generation, and word processing in one software program.

Finally such database managers as Microsoft Access and Visual FoxPro ultimately overtook others.

Word Processing. A major problem for word processing software was the perception that computers calculated and generated reports full of numbers – not words.

The first word processing program that truly established the category was WordStar, introduced in 1979. Throughout the 1980s, different word processors leap forged into prominence with each new release. Magic Wand (1979), Corel’s WordPerfect (1984), Microsoft Multi-Tool Word (1983), and Apple’s Write captured market share as they expanded the uses for word processing programs.

Although each release of word processing programs expanded the capability of this software category, users still remained frustrated when they printed their documents. What they saw on the screen was not what they saw come out of the printer. In 1985, Adobe Systems, Inc. introduced PostScript page description language (PDL), and along with Apple’s

LaserWriter printer created an entire industry and software category called desktop publishing. Together, the PDL and the printer enabled PC users to format a document on the screen exactly as it would appear when printed and introduced a new word – WYSIWYG – What You See Is What You Get. Being able to view a document before printing augmented the creativity of many users.

Before long, word processing programs were capable of more than just manipulating words; the ability to insert pictures, clip-art, and graphs was introduced. But even as programmers continued to respond to the public’s software requests, their insatiable appetite for innovation grew. The popularity of word processing software continued to escalate and more tools were continuously added. Unique tools such as spell-checker, thesaurus, font menus, grammar check, and templates eventually became commonplace. Often times users would find a needed tool in one of their programs but not another, so programmers created suites. Suites typically integrate a word processor with a database manager and a spreadsheet application, so that each program would have the ability to share data with any other program in the package.

Games and Entertainment.Even the first mainframes were used to play games, albeit they were more likely to be thought-provoking chess rather than blood-and-guts Mortal Combat.
The first games were text only programs called Star Trek and Colossal Cave. These were followed by Space War, the first arcade-style game originally played on a mainframe computer at the Massachusetts Institute of Technology.

Early PC games were mostly educational in purpose and less than appealing for people who had grown accustomed to the visual excitement of the dedicated game devices. Gaming on PCs became popular when hardware was able to display high-resolution color, microprocessors could handle the high speed bit rates necessary for the action, and a variety of controllers (joysticks, steering wheels, etc.) were available for PCs.

PC game software falls into several categories. In addition to interactive novels and simulations there are skill and action games and strategy / cognitive games.

The Internet has made a significant impression on computer software’s marketability and capability. A consumer no longer has to go to a store, sift through hundreds of software titles, read descriptions of each to make a purchasing decision, go home and figure out how to install and register the software, and then learn how to use the software before realizing that they may be unsatisfied with their purchase. The Internet has popularized the concept of public domain software. Public domain software is available as either freeware or shareware.

Freeware is software that is distributed to users free of charge. However, there is no guarantee that the program is either useful or error-free.

Shareware is software offered on a «try before you buy» basis so users can determine if it meets their needs. People are encouraged to copy the program and share it with others, always with the understanding that if a user likes the program, then either a donation or a fee is to be paid to the programmer. Users who download freeware and shareware should take caution before using such programs as there is the possibility of acquiring a virus. To protect computer, public domain users should use anti-virus utility software.

The Internet has also introduced a whole set of new apps. E-mail, web browser, firewall, and search engine software are just a few types of apps that are used solely online. HTML (Hypertext Mark-up Language) and Java are just two examples of internet-based computer languages.

2. Exercises

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Infidelity	\|	Read and translate the text.

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