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Of course, there might be more roles involved for large-scale companies (e.g. like a special translater role for enterprises operating in different countries ) however with multi-lingual sites). However, I consider those as more specific roles of the basic ones and thus not explicitly mentioned mention them here.
User Profiles
So far, you should have recognized that I only talked about a user's tasks - the "what" he's doing with the system. But there is definitely more to say about the user of a software system. For example "who" exactly or "when" and "how often" is he performing a specific tasks. These questions don't target the user's tasks but his skills and characteristics.
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