PROGRAMMING LANGUAGES

 

PROGRAMMING LANGUAGES

Computers can perform a variety of tasks. However they cannot perform any of them on their As we know, computers have no commonsense and they cannot think. They need clear-cut instructions to tell them what to do, how to do and when to do A set of instructions to carry out these functions is called a computer program.
The communication between two parties, whether they are machines or human beings. always needs a common language or terminology. The language used in the communication of instructions to a computer is known as computer language or programming language. There are many different types of languages available today. A computer program can be written using any of the programming languages depending upon theaskask to be performed and the knowledge of the person developing the program. The process of writing instructions using a computer language is known as programming or coding. The person who writes such instructions is referred as a programmer.

We know that natural languages such as English, Hindi or Tamil have a set of characters and use some rules known as grammar in framing sentences and statements. Similarly, set of characters and rules known syntax that must be adhered to by the programmers while developing computer programs.

Although, during the intial years of computer programming. All the instructions were written in the machine language, a large number of different type of programming languages have been developed during the last six decades. Each one of them has its own unique features and specific applications. In this chapter. we shall discuss briefly the various types of programming languages, their evolution and characteristics and how they are used to solve a problem using a computer.

HISTORY OF PROGRAMMING LANGUAGES

The history of programming languages is interlinked with the evolution of computer systems. As the computer systems became smaller, faster and cheaper with time, the programming languages also became more and more user friendly. Ada Augusta Lovelace, a companion of Charles Babbage, was considered as the first computer programmer in the history of programming languages. In the year 1843, Ada Augusta Lovelace wrote a set of 'instructions to program the analytical engine designed by Charles Babbage.

This computer program was used to transform the data entered by the users into binary form before being processed by the computer system. This program increased the efficiency and the productivity of the analytical engine by automating various mathematical tasks. Later, in the year 1946, Konrad Zuse, a German engineer, developed a programming language known as Plankalkul. It was developed to target the various scientific, business and engineering needs of the users. It was considered as the first complete programming language that supported various programming constructs and the concept of data structures as well. The various programming constructs were implemented in this programming language with the help of Boolean algebra.

During the 1940s, machine languages were developed to program the computer system. The machine languages which used binary codes Os and 1s to represent instructions were regarded as low-level programming languages. The instructions written in the machine language could be executed directly by the CPU of the computer system. These languages were hardware dependent languages. Therefore, it was not possible to run a program developed for one computer system in another computer system. This is because of the fact that the internal architecture of one computer system may be different from that of another. The development of programs in machine languages was not an easy task for the programmers. One was required to have thorough knowledge of the internal architecture of the computer system before developing a program in machine language.

During the 1950s, assembly language, which is another low-level programming language, was developed to program the computer systems. The assembly language used the concept of mnemonics to write the instructions of a computer program. Mnemonics refer to the symbolic names that are used to replace the machine language code. The programmers enjoyed working with this programming language because it was easy to develop a program in the assembly language as compared to the machine language. However, unlike machine language programs, assembly language programs could not be directly executed by the CPU of the computer system and required some a software program to convert these programs into machine understandable form.
During the period between 1950 and 1960, many high-level programming languages were devel to cater to the needs of the users of various disciplines, such as business, science and engineering 1951, Grace Hopper, an American computer scientist, started working towards designing a compiler calle A-0, and in the year 1957, developed a high-level programming language known as 1952, another programming system known as AUTOCODE was developed by Alick E. Glennie. On Hopper was considered as the first person who had put some serious efforts towards the development of high-level programming language. In the year 1957, another popular high-level programming language known as FORTRAN (FOR TRANStation) was developed. During its era, it was the only high-level programming language became hugely popular among its users. FORTRAN was developed by John Backus and his team International Business Machines (IBM) FORTAN was best suited for solving problems related to scienti and numerical analysis field. Another high-level programming language known as ALGOL (Algorith Language) was developed in the year 1958. Some other high-level languages that evolved during the era were LISt Processing (LISP) in 1958, Common Business Oriented Language (COBOL) in 1959 and ALGOL 60 in 1960.

In the next decade, from 1960 to 1970, more high-level programming languages evolved. In the yea 1964, the Beginners All-Purpose Symbolic Instruction Code (BASIC) was designed by John G. Keme and Thomos E. Kurtz at Dartmouth college. It was a general-purpose programming language that was simple to use. In the same year, another powerful high-level programming language, PL/1 with many rich programming features such as complex data type and methods, was designed for developing engineering and business applications. PLI was considered to have the best features of its ancestor programming languages: COBOL, FORTRAN, and ALGOL 60. The other programming languages that evolved during this era were Simula I, Simula 67. Algol 68 and APL.

The period between 1970 and 1980 was actually the golden era for the development high-level programming languages. This period saw the birth of many general-purpose and powerful high-level programming languages. In the early 1970s, a procedural programming language, Pascal was developed by Niklaus Wirth. This programming language was provided with strong data structures and pointers which helped in utilizing the memory of the computer system in an efficient manner. In the year 1972 Dennis Ritchie developed a powerful procedural and block structured programming language known as C. C is still very popular among the users for developing system as well as application software. In 1974 IBM developed Structured Query Language (SQL) that was used for performing various operations on the databases, such as creating, retrieving, deleting and updating. Apart from these programming languages, some other high-level programming languages that evolved during this era were Forth, Smalltalk and Prolog.

During the next decade, from 1980 to 1990, the focus of development of high-level programming languages shifted towards enhancing the performance and design methodology. The languages of this period used modular approach for designing large-scale applications. The modular approach of program design can be regarded as a design methodology, which divides the whole system into smaller parts that could be developed independently. This approach of designing software applications is still employed by modern programming languages. Some of the high-level programming languages that evolved during this era include Ada, C++, Perl and Eiffel.

The high-level programming languages developed and designed in the 1990s are considered as the fifth generation programming languages. During this period, Internet technology evolved tremendously Therefore, the basic purpose of the programming languages of this period was to develop web-based applications. However, these languages could also be used for the development of desktop applications. Theimportant high-level programming languages of this era are Java, VB and C#. Most of the programming languages of this era employed object-oriented programming paradigm for designing and developing robust and reliable software applications.

GENERATIONS OF PROGRAMMING LANGUAGES
Programming languages have been developed over the years in a phased manner. Each phase of Hevelopment has made the programming languages more user-friendly, easier to use and more powerful. Each phase of improvement made in the development of the programming languages can be referred as a eneration. The programming languages, in terms of their performance, reliability and robustness can be rouped into five different generations.

• First generation languages (1GL)
• Second generation languages (2GL)
• Third generation languages (3GL)
• Fourth generation languages (4GL) • Fifth generation languages.

FAQs

★Why do we need programming languages?
Coding allows people to interact with computers to accomplish desired tasks. Computers don't understand human language, so people use programming languages to translate directions into binary code that devices can follow as apps, websites, and software programs.