Types of Programming Languages

There  are basically two types of computer programming languages given below:

1. Low level language

2. High level language

1. Low Level Languages

The programming languages that are very close to machine code (0s and 1s) are called low-level programming languages. The program instructions written in these languages are in binary form.

The examples of low-level languages are:

• Machine Language

• Assembly Language

I. Machine Language

The instructions in binary form, which can be directly understood by the computer (CPU) without translating them, is called a machine language or machine code. Machine language is also known as first generation of programming language. Machine language is the fundamental language of the computer and the program instruction in this language is in the binary form (that is 0's and 1's).

• This language is different for different computers.

• It is not easy to learn the machine language.

Advantage of Machine Language

The only advantage of machine language is that the program of machine language runs very fast because no translation program is required for the CPU.

Disadvantage of Machine Language

Here are some of the main disadvantages of machine languages:

• Machine Dependent - the internal design of every computer is different from every other type of computer, machine language also differs from one computer to another. Hence, after becoming proficient in the machine language of one type of computer, if a company decides to change to another type, then its programmer will have to learn a new machine language and would have to rewrite all existing program.

• Difficult to Modify - it is difficult to correct or modify this language. Checking

machine instructions to locate errors is very difficult and time consuming.

• Difficult to Program - a computer executes machine language program directly

and efficiently, it is difficult to program in machine language. A machine

language programming must be knowledgeable about the hardware structure of

the computer.

II. Assembly Language

It is another low-level programming language because the program instructions written in

this language are close to machine language.

Assembly language is also known as second generation of programming language.

With assembly language, a programmer writes instructions using symbolic instruction

code instead of binary codes.

Symbolic codes are meaningful abbreviations such as SUB is used for substation

operation, MUL for multiply operation and so on. Therefore this language is also called

the low-level symbolic language.

The set of program instructions written in assembly language are also called as

mnemonic code.

Assembly language provides facilities for controlling the hardware.

Advantage of Assembly Language

Here are some of the main advantages of using assembly language:

• Easy to understand and use

• Easier to locate and correct errors

• Easy to modify

• Efficiency of machine language

Disadvantage of Assembly Languages

And here are some of the main disadvantages of using assembly language:

• Machine dependent - each instructions of assembly language program is

translated into exactly one machine language instruction, an assembly language

programs are dependent on machine language.

• Knowledge of hardware required - assembly languages are machine dependent,

an assembly language programmer must have a good knowledge of characteristics

and logical structure of his/her computer to write a good assembly language

computer code.

• Machine level coding - assembly language instruction is substituted for one

machine language instruction. Hence like machine language programs, write

assembly language program is also time consuming and difficult.

2. High Level Languages

The programming languages that are close to human languages (example like English

languages) are called the high-level languages.

The examples of high-level languages are:

• Fortran

• COBOL

• Basic

• Pascal

• C

• C++

• Java

The high level languages are similar to English language. The program instructions are

written using English words, for example print, input etc. But each high level language has

its own rule and grammar for writing program instructions. These rules are called syntax of

the language.

The program written in high level language must be translated to machine code before to run

it. Each high level language has its own translator program.

The high level programming languages are further divided into:

• Procedural languages

• Non procedural languages

• Object oriented programming languages

Advantages of High Level Languages

There are several advantages of high level programming languages. The most important

advantages are:

• Easy to learn - the high level languages are very easy to learn than low level

languages. The statements written for the program are similar to English-like

statements.

• Easy to understand - The program written in high level language by one

programmer can easily be understood by another because the program instructions are

similar to the English language.

• Easy to write program - In high level language, a new program can easily be written

in a very short time. The larger and complicated software can be developed in few

days or months.

• Easy to detect and remove errors - The errors in a program can be easily detected

and removed. Mostly the errors are occurred during the compilation of new program.

• Built-in library functions - Each high level language provides a large number of

built-in functions or procedures that can be used to perform specific task during

designing of new programs. In this way, a large amount of time of programmer is

saved.

• Machine Independence - Program written in high level language is machine

independent. It means that a program written in one type of computer can be executed

on another type of computer.

Limitation of High Level Language

There are two main limitations of high level languages are:

• Low efficiency - a program written in high level languages has lower efficiency than

one written in a machine/assembly language to do the same job. That is, program

written in high level languages result in multiple machine language instruction that

may not be optimize, taking more time to execute and requiring more memory space.

• Less flexibility-  high level languages are less flexible than assembly languages

because they do not normally have instructions or mechanism to control a computer's

CPU, memory and register.

a) Procedural Language

Procedural languages are also known as third generation languages (3GLs). In a procedural

language, a program is designed using procedures.

A procedure is a sequence of instructions having a unique name. The instructions of the

procedure are executed with the reference of its name.

In procedural programming languages, the program instructions are written in a sequence or

in a specific order in which they must be executed to solve a specific problem. It means that

the order of program instructions is very important.

Some popular procedural languages are described below:

• FORTRAN - IT stands for formula translation. It was developed in 1957 for IBM

computers. It was the first earliest high level programming language used to introduce

the concept of modular programming. It has been revised many times. Its commonly

used version is FORTRAN 77

• COBOL - IT stands for common business oriented language. It was developed in

1959. This high-level language was specially developed for business and commercial

applications. It was suitable for handling large amount of data such as:

o To prepare payroll

o To process credit and debit account

o To control inventory system and many other business applications

• Pascal - THIS programming language is named in the honour of Blaise Pascal, a

mathematician and scientist who invented the first mechanical calculator. Structured

programming language and is popular in computer science development in 1971. It is

suitable for scientific field.

• ADA - It is developed in 1980 and is named in the honour of Lady Augusta ADA.

She was the first computer programmer. The high level structure language Pascal was

used as a model for the development of ADA language. This language is mainly used

for defence purposes such as for controlling military weapons like missiles etc.

• C language - Dennis Ritchie and Brian Karnighan developed it in 1972 at Bell

Laboratories. It is a high level language but it can also support assembly language

codes (low level codes). It is because, C language is also referred to as middle level

language. The program written in C can be compiled and run on any type of

computer. In other words programs written in C language are portable. C language is

a structured programming language. The main feature of C language is that, it uses a

large number of built-in functions to perform various tasks. The user can also creates

its own functions.

b) Non Procedural Languages

Non procedural programming languages are also known as fourth generation languages. In

non procedural programming languages, the order of program instructions is not important.

The importance is given only to, what is to be done.

With a non procedural language, the user/programmer writes English like instructions to

retrieve data from databases. These languages are easier to use than procedural languages.

These languages provide the user-friendly program development tools to write instructions.

The programmers have not to spend much time for coding the program.

The most important non procedural languages and tools are discussed below:

• SQL - it stands for structured query language. it is very popular database access language

and is specially used to access and to manipulate the data of databases. The word query

represents that this language is used to make queries (or enquiries) to perform various

operations on data of database. However, SQL can also be used to create tables, add

data, delete data, update data of database tables etc.

• RPG - it stands for report program generator. This language was introduced by IBM to

generate business reports. Typically, RPG is used for application development on IBM

midrange computers, such as AS/400.

c) Object Oriented Programming Languages

The object oriented programming concept was introduced in the late 1960s, but now it has

become the most popular approach to develop software.

In object oriented programming, the software is developed by using a set of interfacing

object. An object is a component of program that has a set of modules and data structure. The

modules are also called methods and are used to access the data from the object. The modern

technique to design the program is object oriented approach. It is a very easy approach, in

which program designed by using objects. Once an object for any program designed, it can

be re-used in any other program.

Now-a-days, most popular and commonly used object oriented programming (OOPs)

languages are C++ and Java.