iphone - what is target id in this code -

What is the target ID, what is the data type of the application ID or what is it.

  NSString * message = @ "test message here"; NSMutableDictionary * params = [NSMutableDictionary dictionary]; [Parameter set object: for message: @ "message"]; [Parameter set object: toID forKey: @ "target_id"]; [[Delegate with the FBRAccount Request: Self] Call: @ "facebook.Stream.publish" parameter: Parameters];  

Please answer shortly.

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