Structured and Modular programming.
Structured programming means the collection of principles and practices that are directed toward developing correct programs which are simple to maintain and simple to understand. It should read like a sequence from starting to end instead of branching from later statements to previous ones and back again. While in modular programming the modularity of a system can be shown by a hierarchical structure which has a one main module at level 1 and gives a brief explanation of the system. At level 2 the major module refers to a number of sub program modules the give a more detailed explanation of the system and so on. A significant aspect in this hierarchical structuring process is the want to understand a module at a particular level independently of all other modules at the similar level.