Procedural oriented programming

Procedural oriented programming (pop):-

A program in a procedural language is a list of instruction where each statement tells the computer to do something. It focuses on procedure (function) & algorithm is needed to perform the derived computation.

When program become larger, it is divided into function & each function has clearly defined purpose. Dividing the program into functions & module is one of the cornerstones of structured programming.

E.g.:- c, basic, FORTRAN.

Characteristics of Procedural oriented programming:-

1. It focuses on process rather than data.
2. It takes a problem as a sequence of things to be done such as reading, calculating and printing. Hence, a number of functions are written to solve a problem.
3. A program is divided into a number of functions and each function has clearly defined purpose.
4. Most of the functions share global data.
5. Data moves openly around the system from function to function.

Drawback of Procedural oriented programming (structured programming):-

1. It emphasis on doing things. Data is given a second class status even through data is the reason for the existence of the program.
2. Since every function has complete access to the global variables, the new programmer can corrupt the data accidentally by creating function. Similarly, if new data is to be added, all the function needed to be modified to access the data.
3. It is often difficult to design because the components function and data structure do not model the real world.

For example, in designing graphics user interface, we think what functions, what data structures are needed rather than which menu, menu item and soon.

4. It is difficult to create new data types. The ability to create the new data type of its own is called extensibility. Structured programming languages are not extensible.

To overcome the limitation of Procedural oriented programming languages Object oriented programming languages were developed.