"The 3 Commands"
Command System - organizational structure to help organize an incident.
Command Function - a function inside the Command System.
Command Team - a group of people trained in the Command System and help staff the Command System. Most will operate in the Command function of the system but you will find parts of the Command Team scattered in the higher ranks of all 5 functions of the Incident Command System.
The Command function assumes all responsibilities of the incident. They also oversee the other 4 functions of the ICS. A Single Command is when only one agency is involved. This occurs when CDF has complete control over the incident and there is no BLM or USFS responsibilities in the incident. Other agencies may still be involved such as law enforcement or the Red Cross but they will have agency representatives in the Command Team only. A Unified Command occurs when more than one agency's boundery has been crossed. In our case, a CDF fire burns into a National Forest and the USFS then becomes the majority of the Incident Command System.
The Incident Commander is the person in charge of the entire incident. Underneath the IC is their "Command Staff" much like the President's cabinet. The Command Staff and the IC together make the Incident Command Team. The Command Team may also include the top person from each of the other 4 areas of ICS; Operations, Planning/Info, Logistics and Finance. While Command Teams are usually built on the fly as an incident unfolds, if the incident is prolonged, they will call in "pre-determined" Command Teams that are known to work together and train together. This ensures a smooth transition from one team to another.
The goal of the Incident Command Team is to start at the bottom of the pyramid and understand the agency's policy and direction. In CDF's sense that is to protect life, property and assets. Then they will establish incident objectives and goals based on those policies and directions. After making the objectives they will select the appropriate strategy for the incident. Then the actual firefighting - they will perform those tactical directions until they finally achieve the goal they established earlier.