Reproduction is something that is general to living organisms and it is part of many things that classifies a man or an organism to be a living thing. Reproduction can be defined as the biological process in which living things are able to produce a replica of them. In man, you are biologically fit to give birth to a child only when your reproductive organs are matured enough to do so.
The primary reason for reproduction is to ensure a regular sequence of existence of various animal species. Reproduction will prevent certain animal species from going into the extinction. Just imagine a world where the word 'Reproduction' has never been heard, you should expect a total extinction of every living thing. The earth is designed in a way that it ensures the continuous existence of different species in it. Reproduction makes it possible for us to be having a succeeding generation.