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A guideline is an intermediary step that acts as a suggestion. 

Guidelines often are not rules but rather strong hints that users should follow. 

For example, a guideline can provide a template for new policies. While following such a guideline is not required, if all policies are created using the principles the guideline provides, employees would be able more easily to learn the general format of a policy and locate the desired information. On the other hand, not following the guideline to create a new policy would not break a rule or require punishment