1) Informing 2) Making known 3) Oral summary 1) Instructions 
A description or discussion of rules and guidelines for a class. The briefing might be written and posted, delivered orally by the judge, or both.
The pre, during and post flight informative and safety instructions.
[n] - detailed instructions, as for a military operation
briefing The action of giving information or instructions relating to a particular situation; information of this kind.
noun detailed instructions, as for a military operation
a short, factual oral summary of the details of a current or projected military operation given to the participants or observers. · any set of concise instructions or a summary of events.