Skip to main content

Program language


Program language
 The instructions are written (or coded) in some programming language, is executable by a computer to perform a specific task. A Programming language is a formal language which specifies a set of instructions and the rules of their application. By the correct use and combination of the instructions we can create our programs.
A lot of programming languages have been developed since the beginning of computer science and the development has not finished at all. Actually, a continuous development is going on in the world of programming languages.
Programming languages may be classified into programming language generations. This classification tries to mirror the development in programming styles and languages. Programming language generation,
 First generation languages (1GL):
 Numerical machine code languages are regarded as the lowest-level programming languages (lowest abstraction level). The instructions are actually binary numbers which can be expressed in octal or hexadecimal format to reduce the length of instructions in a program.
These programming languages are hardware-dependent which means that the instruction set is specific to a class of processors using the same hardware architecture. For example, the machine code 00000101 causes the CPU to decrement the numeric value actually held by B processor register in the case of a Zilog Z80 processor.
 Second generation languages (2GL):
An assembly language program is shorter than its correspondent machine code program. Unlike a machine code program, an assembly language program cannot be executed directly by the CPU. A special utility program called assembler is used for converting the source code into a machine code program.
They were mostly used in the 1950-s an 1960-s. Until recently, assembly languages were used for writing low level, simple but efficient programs for specific hardware such as industrial microcontrollers or mobile phones. Because of the luck of higher abstraction level statements (loops and conditional branches), writing a larger and more complex program is slow and hard. This is the main reason why their use is declining. Programming language generation PDP-11 minicomputers (1970) manufactured by Digital Equipment Corporation (DEC).
Third generation languages (3GL):
They are also called high level languages. The abstraction level of these languages was raised by introducing several new and useful elements in programming. Their most important features are the application of different data types and structures (e.g. integer, float, double, arrays), control structures (conditional branches, loops), several operators (arithmetic, relational and logical operators). Due to these innovations the program development became significantly easier and faster.
 Fourth-generation languages (4GL):
The main purpose of designing newer languages with higher abstraction level was facilitating and accelerating the process of software development. 4GL languages are also known as very high level languages because a single 4GL instruction may replace several 3GL instructions, so the source codes are shorter and more similar to a text written in a natural language (generally in English) than those of 3GL languages.
Most of them are aimed at solving specific problems (domain specific languages). Programming language generation Fourth-generation languages (4GL) For example: SQL is a language to query databases, Oracle Reports is a language to make reports.
Fifth Generation languages (5GL):
The components of a program, the connections of the components, the operations and the control flow of the operations can be represented by graphical objects. And the suitable arrangement of the required elements forms the program.
The development environment converts the graphically edited program into the source code of a 3GL or 4GL language. These languages are mostly domain specific. Programming paradigms Programming paradigm is an approach of programming which is supported by a set of theories, models and methods used in programming.

Comments

Post a Comment

Popular posts from this blog

Characteristics of computers

    Characteristics:        All computers have similar characteristics, which tells how computers are efficient to perform task. Computers have some Limitations also. Speed:     Computer can work very fast. It takes only few seconds for calculations on very large amount of data. Computer can perform millions (1,000,000) of instructions per second.      We measure the speed of computer in terms of microsecond (10-6 part of a second) or nanosecond (10 to the power -9 part of a second).   Accuracy:        The degree of accuracy of computer is very high and every calculation is performed with the same accuracy.  The errors in computer are due to human and inaccurate data.       The calculation done by computer are 100% error free, If we provide accurate input. Diligence:        A computer is free from tiredness, lack of concentration...
18 comments
Read more

DS LAB FOR II YEAR

1.SINGLE LINKED LIST Procedure for creation of single linked list: STEP-1 : Declaring a variable named as “item”.Ie the element what we place in the linkedlist of the new node.         STEP-2 : Read the value   in “item”. Set first=last=null and next=null. STEP-3: Create a new node named as temp and assign the variable item to data part andassign Address of the node temp to null.       temp.data=item;       temp.next=null; STEP-4: Check   the address part of the first node Check if first=null Then assign first=last=temp Other wise Then assign the new node tolast.next=temp          last=temp STEP-6 : Repeat STEP-3 until you read required nodes. Procedure for display the linked list: STEP-1 : Check whether the list having nodes or not i.e Check if first=null        ...
26 comments
Read more

LEVELS AND CURVES

LEVELS:                 Levels are used to set the shadows, mid tone etc.  O pen an image on Photoshop window. Select image menu on menu bar than adjustments than levels. A dialogue box will appear on screen which shows three pointers which indicates three optimum. The black triangle indicates shadows and gray triangle indicates mid tone and white triangle indicates highlights. In the channel menu different options are provided in drop down list. Make sure select on preview, which gives current adjustments on your picture. CURVES: Curves are to  similar to levels, it gives more power to control shadows highlights and mid tones. One of the simplest adjustment we can make with curves is increasing the contrast. Go to image menu and than adjustments,than curves. Dialogue box will appear on screen with straight diagonal line.      ...
16 comments
Read more