This document provides an overview of haemostasis (hemostasis). It begins by defining haemostasis as the physiological process involving cells, soluble factors, and proteins that maintains blood in a fluid state and arrests bleeding after trauma. It then describes the two types of haemostasis - primary (formation of platelet plug) and secondary (coagulation protein-mediated). The document outlines the process of haemostasis including vasoconstriction, platelet plug formation, activation of coagulation, and plug dissolution. It also discusses coagulation factors, laboratory tests, haemostatic agents, and bleeding disorders.