Programming Language used today | Computer Science for Class 7 PDF Download

Introduction

What is Programming Language?
It is a Language we used to communicate with Computers. There are lot of programming languages with its own purposes and syntax. Coded language used by programmers to write instructions that a computer can understand to do what the programmer or the computer user wants.

Why we need Programming Languages?
It is because Computer does not have a brain to take its own decisions and act accordingly. It does not have the capability to respond to the directions and instructions given by the human beings in their language. It needs to be programmed before use. We need a different Language to Communicate with the Computers. These are known as Computer Programming Languages. Program is a set of instructions given to the Computer so that it can handle different situations and scenarios.

How a Computer Program works?
Computer is having a Microprocessor made of millions of transistors. It can handle basic logical and arithmetic operations and accept different inputs and produce different outputs. A Microprocessor is having all resources for handling data, performing logical and arithmetic operations on the data, produce different output based on the operations in it and to control different input output peripherals connected to it. Now programs are instructions which describe the sequence and use of different resources in the Microprocessor to carry out certain tasks.
The Language used to program a Microprocessor is called Machine Level language, which is the very basic Computer Programing Language. It is also known as Binary Level Language (A Language composed of only 1s and 0s). However it is a tedious task to program a computer using Machine Level Language as it lengthy, time consuming and complex. However we should remember that the old computers were programmed using this Language.
To make Programming easier, an Assembly Level Language is introduced. These are certain English words used to Program and process data in a Micro Processor. The Assembly Level Languages are converted into Hex Code (A number system with base 16) using a compiler. An assembler is a program which converts the Machine Code into Hex Code.
Then comes the Middle Level Language. The main purpose of these language is to make programing easier and less complex. These programs are easily understandable by human being. However the Microprocessor in Computers can understand only Machine Level Languages. Now who will translate the Middle level Languages to Machine Level Languages? The Software used to convert the middle level language into Machine Level language is called Compiler. Interpreter is another Software which is used to Execute the Computer Program directly without converting it into Machine Level Language. Debugger is a Software used to check the syntactical mistake (grammar mistakes in Computer Programming) in Middle Level Language before converting it into Machine Level Language.
There are different High Level languages which makes the programming more easier as its syntax and usage of words are almost similar to common English Language. However the pain of conversion of this High Level Language to Machine Level Language will be handled by the Compiler.

• Some Low Level Languages: PL/S, BLISS, BCPL, ALGOL, C
• Some Middle Level Languages: C#, C++, Java,
• Some High Level Languges: Python, Ruby, and CommonLisp, SQ
• Some Web Designing Languages: PHP, Rub
• Some Hardware Design Languages: VHDL, Verilog (This Program is exclusively used to design Integrated Circuits(IC Chips))

Types of Languages

• Easier to learn and understand.
• Less time to write program.
• Easier to maintain.

Disadvantage of high-level language

• It takes more time to execute the program.
• Difficult in debugging if proper code is not available.
• Inability to perform all operations because cannot manipulate bits and registers.

Machine Level Language
Machine level language is a machine language that a computer can understand directly without any difficulty. It is made up of series of 1’s and 0’s. The order of the bits serves as a code specifying what the computer should do.

Advantages

• Computer directly understands the code written in this language therefore execution speed is fast and use of primary memory.

Disadvantages

• Difficult to learn and program.
• The program becomes very lengthy and difficult to locate the errors.
• difficult to debug.

Programs written in machine language in one machine cannot be easily transferred to other machines.

Assembly Language
Assembly language is the language that permits the use of mnemonics for each instructing that the machine can do. The program written in assembly language must be transmitted to machine understandable form, which is done by assembler because computer cannot understand mnemonics codes(alphabetic codes) such as ADD for addition, SUB for subtraction etc. The program written by the programmer in assembly language is called a source program. The program, which is obtained after being converted into machine language, is called object program. It is also machine-oriented language ie. Designed for specific make and model of a computer.
Advantages

• Simple to understand and use when compared to machine level language.
• Less time is required to write the program
• Program debugging is easier

Disadvantages

• It is machine dependent i.e. each design of machine has a different assembly language.
• Assembly level language is too difficult to understand than the high level language.
• Coding in this language is time-consuming.

Many, many different high-level languages have been developed, e.g.:
Fortran(1954), Lisp(1958), COBOL(1959), Simula(1964), Basic(1964), Smalltalk(1969), Prolog(1970), Pascal(1970), C(1971), ML(1973), Scheme(1975), Ada(1979), C++(1983), Perl(1987), Python(1991), Java(1995), C#(2000), VB.NET(2001)
There are some high level programming languages:
Query languages
Query languages allow the user to ask questions about, or retrieve information from database files by forming requests in normal human language statements (such as English). The difference between the definitions for query language and for database management systems software is so slight that most people consider the definitions to be the same. Query languages do have a specific grammar vocabulary, and syntax that must be mastered, but this is usually a simple task for both users and programmers.

JavaScript
JavaScript is a very prominent coding language for websites that first appeared in 1995. It is a high-level interpreted scripting language. Its main platform is web browsers, but it’s also gained recent popularity on web servers through Node.js.

Python
Python is a high-level interpreted coding language that runs on a range of different platforms. It was created in 1991 by Guido van Rossum. Python was designed to emphasize code readability, with clear and expressive syntax. A lot of people choose to learn Python first for this very reason.

SQL
SQL stands for Structured Query Language. It’s been used to interact with databases since 1974. SQL code is often written as standalone lines known as queries. Each query is designed to either create, read, update or delete data in a database.

PHP
PHP is a coding language for producing dynamic web pages. It was created by Rasmus Lerdorf in 1995. It has the abilities to send SQL queries and to output HTML, and can be described as the link between the database that stores all the content on a site, and the HTML that lets you view it.

C++
C++ is an enhanced version of C that adds the object-oriented paradigm. It was created by Bjarne Stroustrup in 1979. C++ is a compiled language and runs on multiple hardware platforms.
Fortran: Formula translation
COBOL: Commonly business oriented language (It is commonly used for business purpose)

Visual Basic
Visual Basic is another Microsoft language, developed in 1991. It is an event-driven language, meaning it’s designed to respond to user events such as mouse clicks or key presses. Visual Basic is a high-level compiled language and its platform is Windows.

Java
java is a ubiquitous coding language designed for cross-platform compatibility. It was developed by Oracle Corporation and first appeared in Java is a high-level compiled language and is designed to run on just about any operating system.

Perl
Finally, Perl is a web language that was developed by Larry Wall in It’s a powerful and practical language that was originally designed for text processing. Perl has been called ‘the duct tape that holds the Internet together’, referring to its power and perceived ugliness.