Haemorrhage, or bleeding, occurs when blood escapes from blood vessels into surrounding tissue. Uncontrolled haemorrhage can result in excessive blood loss and shock. Haemorrhage is classified based on the type of vessel involved (arterial, venous, capillary), timing (primary, reactionary, secondary), location (external, internal), and duration (acute, chronic). Haemorrhagic shock is a condition of reduced tissue perfusion resulting from inadequate oxygen delivery. Management of haemorrhage involves general measures like oxygen administration and specific measures such as pressure and packing, positioning, tourniquets, and surgical techniques like ligation or cauterization to control bleeding.