A computer cannot work by itself. It has to be instructed to perform a task, using a language which it can understand. A machine can understand only 0’s and 1’s. But it is very difficult for the user to create instructions, or programs using 0’s and 1’s. In order to make the process easy, scientists have developed a high level language, which uses simple English for programming. The programs written in high level language are then translated in to machine language or low level language by a compiler.
Features of high level language:
A high level language is very user friendly.
Enables programmer to write in simple English and mathematical notations.
The languages are machine independent. Hence they can be executed on different machines.
All these programs require compilers to translate the program in to machine understandable form, vice versa.
COBOL, Pascal, FORTRAN are the some of the examples of high level languages.
Advantages:
Uses simple mathematical and lain expressions making it easy to learn them. They are procedure oriented; hence they take less time to write.
Easy to test and correct errors.
Program in this language can be written without the knowledge of internal structure of the computer.
High level language programs are machine independent. They can be written on any computer and can be used on any computer.
Easy to make modifications in the program.
Disadvantages:
Programs written in high level languages are less efficient in the use of CPU and facilities. As they are not in machine understandable form, the program is first converted in to machine understandable form and then it is executed.
Runs slower due to the generality of statements and the fact that they are portable between different machines provided a suitable compiler is available.
As the program is written in high level language, it needs a compiler to translate the program in to machine understandable form and the compiler occupies enough of memory space, and the memory space available to the program is reduced.
Examples of high level languages are:
BASIC (Beginners all purpose symbolic instruction code), COBOL (Common business oriented language), PASCAL, FORTRON (Formula Translator), PL/I (Programming Language), ALGOL.