This article discusses inflammation as an important protective-adaptive reaction of the body that develops in response to harmful factors (infection, mechanical damage, chemical and physical effects). The main stages of the inflammatory process, pathophysiological mechanisms, and the role of cellular and humoral factors are analyzed. Also, the positive and negative aspects of inflammation, acute and chronic forms, and their clinical significance are considered. The article serves as a theoretical basis for medical workers and students to better understand the inflammatory process and correctly assess it.