By Ashraf Al Shafaki
There are two methods for developing any product or artifact: sequential and iterative.
Using a sequential model to develop a product means you follow a number of stages one after the other in sequential order. Once you have completed a stage and started the stage following it there is no going back. You cannot go back to the previous stage which you have already completed to make any changes.
After going through all the stages of the process you will then have a complete product or artifact.
In contrast to the sequential model, the iterative approach uses a less rigid and more flexible method. You start by creating a seed of the product. You can start at any 'stage' you like. You then move along any of the other 'stages' in any sequence you prefer. At the end of an iteration, you have a fully working product except that it might not be fully developed or having high capabilities yet. You then go through a second iteration to further develop the product.
After several iterations the product starts to get better and better and can be put in production and used. Even after the product is being used it can still go through further iterations in improve it even better.
The iterative approach has the following benefits over the sequential one:
The iterative method can be used for: