Types of users
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Identify three types of users
The next one implies all previous ones due to required knowledge

Add figure showing the hierarchy maybe?

Modeller
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Explain the job of the modeller

Language Engineer
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Explain the job of the language engineer
Explain why this includes all knowledge of the modeller as well, though in a different domain

Developer
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Explain the job of the developer
Explain why this includes all knowledge of the modeller and language engineer as well, though in a different domain