A Communications Officer will answer your call and ask you several questions about your emergency. Based on the nature of the emergency, the dispatcher will summon police, fire, or emergency medical response. When you call 911, tell the dispatcher your exact location, or as much information about your location as possible, the nature of the emergency (someone has a gun, my house is on fire, my neighbor collapsed, etc.), how many people are injured, if any, and names and descriptions of the people involved in the emergency. Answering these questions does not delay the response since the dispatcher will enter your situation in the system as soon as basic information such as location is provided.
Answering the additional questions ensures you get the best response to your situation. Adding any conditions which could make the situation unsafe for responding personnel or bystanders (weapons, gas leaks, disabled vehicles, animals, etc.) is beneficial as well.
Stay on the line until the dispatcher hangs up. You may be able to provide the dispatcher with additional information as emergency personnel respond, or the dispatcher may be able to provide you with emergency instructions.