The Historical Security Council is essentially the SC (i.e. one of the six main organs established by the UN Charter). The main difference is that it is set in 1968 and therefore it is tasked with addressing issues regarding conflicts from that time period. The purpose of this committee is to seek innovative and collaborative solutions to these historical events in order to set precedent for similar conflicts that may occur in the future or may already be occurring in the present.
All members of the United Nations agree to accept and carry out the decisions of the Security Council. While other organs of the United Nations make recommendations to member states, only the Security Council has the power to make decisions that member nations are then obligated to implement under the Charter. It only has 15 members, including the P5 nations. For more information, go to: http://www.un.org/en/sc/