<unk>  (from ) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants, and is a protective response involving immune cells, blood vessels, and molecular mediators. The function of<unk>  is to eliminate the initial cause of cell injury, clear out necrotic cells and tissues damaged from the original insult and the inflammatory process, and initiate tissue repair. The five cardinal signs are heat, pain, redness, swelling, and loss of function (Latin calor, dolor, rubor, tumor, and functio laesa).<unk>  is a generic response, and therefore it is considered as a mechanism of innate immunity, as compared to adaptive immunity, which is specific for each pathogen. Too little<unk>  could lead to progressive tissue destruction by the harmful stimulus (e.g. bacteria) and compromise the survival of the organism. In contrast, too much<unk> , in the form of chronic<unk> , is associated with various diseases, such as hay fever, periodontal disease, atherosclerosis, and osteoarthritis.<unk>  can be classified as either acute or chronic. Acute<unk>  is the initial response of the body to harmful stimuli, and is achieved by the increased movement of plasma and leukocytes (in particular granulocytes) from the blood into the injured tissues. A series of biochemical events propagates and matures the inflammatory response, involving the local vascular system, the immune system, and various cells within the injured tissue. Prolonged<unk> , known as chronic<unk> , leads to a progressive shift in the type of cells present at the site of<unk> , such as mononuclear cells, and is characterized by simultaneous destruction and healing of the tissue from the inflammatory process.<unk>  has also been classified as Type 1 and Type 2 based on the type of cytokines and helper T cells (Th1 and Th2) involved.<unk>  is not a synonym for infection. Infection describes the interaction between the action of microbial invasion and the reaction of the body's inflammatory response—the two components are considered together when discussing an infection, and the word is used to imply a microbial invasive cause for the observed inflammatory reaction.<unk> , on the other hand, describes purely the body's immunovascular response—whatever the cause may be. But because of how often the two are correlated, words ending in the suffix -itis (which refers to<unk>  are sometimes informally described as referring to infection. For example, the word urethritis strictly means only "urethral<unk> ", but clinical health care providers usually discuss urethritis as a urethral infection because urethral microbial invasion is the most common cause of urethritis. However, the<unk> -infection distinction becomes crucial for situations in pathology and medical diagnosis where<unk>  is not driven by microbial invasion, such as the cases of atherosclerosis, trauma, ischemia, and autoimmune diseases (including type III hypersensitivity).
Inflammation
Transflammation
Calcification
Allergic inflammation
Necrosis
Demineralization 
Neuroinflammation
Cytostasis