What entities have been identified in the budget management system? How are the project and budget related?

The key entities typically distinguished in a budget management system are:

• Project — the main unit of work for which a budget is formed.
• Budget — a financial plan associated with a project, including expense and income items.
• Budget item — a specific category of expenses or income (e.g., salary, equipment).
• User/Role — individuals involved in managing the project and budget.

The relationship between a project and a budget is that the budget is created and maintained specifically for a particular project. The project defines the goals and objectives, while the budget provides the financial resources needed to achieve them. Thus, the budget is an attribute of the project and reflects financial planning and control within the scope of that project.