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Use a different template per category.: A template can be linked to a category. A template can be used to pre-define certain fields, when creating an object of that category. For example, when creating a new request in a certain custom category, the field ‘concerns’ (Problem type) automatically needs to be a specific type of problem.
Different authorizations: Different categories also allows allow the administrator via customization to set different authorizations. For example, a certain custom contract category might be authorized in such a way that only a subset of users managing all the contracts can view or edit contracts in this categoriecategory.