A notification letter is to inform the other party about the situation. The text of the notification letter usually includes two contents: one is to inform the reason and explain the reason for sending this letter; The other is to inform the other party of the specific content of the relevant matters and the problems that should be paid attention to.

A circular letter is a document that forwards the official documents of the same level or different lower-level organs, issues the relevant official documents of the higher-level or the same-level organs, approves the official documents of the lower-level organs, conveys the instructions of the higher-level organs, appoints and dismisses cadres, issues laws and regulations, and requires the lower-level organs to handle, implement or know matters.

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