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A viewpoint is simply a description of the what the stakeholder sees. In order to define this stencil, you must clearly understand their concern. It is a stencil that can be reapplied in time and time again in different contexts resulting in different views. So the view is what you see and the viewpoint is the description of what you see, your perspective! So the full definition of a viewpoint is that it is a way to articulate the concern(s) of stakeholder(s), so it is comprised of three parts, the stakeholder, the concern and the modelling technique.
Examples
UML Class Diagram (
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the technique)
Stakeholders - business analysts, software engineers, developers, business users
Concerns - what are the core/detailed elements of the systems, want to understand system patterns, want to understand the relationship between things in a system
UML Class Diagram (view)
Theatre booking system
BPMN (
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the technique)
Stakeholders - business analysts, software engineers, developers, business users
Concerns - capture current and target business processes, uncover hidden processes, see how processes interact with different parts of a business, understand the information exchanged with a process
BPMN (view)
Withdrawing money at the till at a Bank
A Payment System
Electronic Schematics (
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technique)
Electronic Schematic (view)
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