The structured programming refers to the process in which we break the overall job down into separate pieces of modules.The modules are further can be broken into smaller sigments or pieces which are known as submodules . Modules must be chosen in such a way that we can specify how there is a contact between each pair of modules. This specifies two things:- 1] What the module will do? 2] What assumptions is it making about the behaviour of the other modules? In particular, we must specify what inputs a particular module is to recieve from the various other modules and what outputs it is required to provide for them. In other words, structured programming is a subset of procedural programming that enforces a logical structure on the program being written to make it more efficient and easier to understand and modify. Structured programming frequently employs a top-down design model,in which developers map out the overall program structure into separate subsection