INTRODUCTION

The unified modeling language (UML) is a standardized language for modeling software systems. Although small systems are easy for a single person or a small group to comprehend and develop, large systems are more difficult to design successfully, since there are often many people and entities controlling different aspects of the system and defining how they should work from their own professional specialty or prerogative. For example, a large company requesting a new piece of software might assign the job to a project manager who has a thorough understanding of the overall system requirements, whereas a software developer assigned to work on the system is likely to care more about the ways that individual portions of a system work on a detailed level and less about the practical requirements of users and management. Similarly, an end user of the system is likely to care about how the user interface is organized and that the software is built to facilitate ease of use for everyday users, rather than that a particular software component was designed exquisitely or that the project fulfills the stated requirements that its originator decided on.