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Lesson 2 Project context
Objective Define project context and how it affects the modeling process.
Defining context
Defining your project's context requires that you closely examine the problem statement and then ask yourself and others the right questions.
A good place to begin is to ask why the system is needed.
Who will potentially benefit from the system?
How does this system fit together with other systems? The answers to these questions will allow you to establish a context for your system in relation to the people and systems that need to interact with it.
Project context can radically affect the analysis and design models that you create. For example, creating a model that represents cars and customers sounds simple, right? But a model of a car dealership would be much different than a model of a motor vehicles office or a valet parking company. In each of these contexts, "car" and "customer" refer to a very different set of relationships and behaviors.
The project context is the environment in which the project is undertaken and includes many influences and are generally grouped under external and internal headings.


Unified Modeling LanguageUnified Modeling Language
The car and customer example illustrates how radically context can affect vocabulary. Later in this module, you will learn how to use the data dictionary to define the meaning of the problem domain vocabulary.
To define project context, ask these three questions:
  1. Who will interact with the system?
  2. Which other systems or devices will interact with the system?
  3. How will the users communicate with the system? That is, what information do they need from the system and what information does the system need from them?
Your job is to sift through the volumes of information that usually come in the problem statement and any discussions you have with the users. Doing so will help you find the answers you need to establish the system context. Listen for user answers to the three questions listed above. Better yet, if you have the option, structure your user interviews to focus on these questions.
Later in this module, you will use the use case model to record the responses to your queries in detail, but for now, you simply need to understand where your system fits in relation to the people and systems that need to interact with it.

Project Context - Exercise
Click the Exercise link below to select statements that help you define the context of the course project system.
Project Context - Exercise