What I learnt today in a basic first aid assistance:
D - Danger (Assess the scene for any danger)
R - Response (Assess casualty)
A - Airway (Open and clear airway)
B - Breathing (Check breathing & Give initial breaths)
C - CPR (Perform CPR)
D - Defibrillation (Apply defibrillator)
A CPR is done on a 30 compression to a 2 breathing basis.