Hyperbaric medicine is the branch of medicine that utilizes 100% oxygen at an ambient pressure higher than sea level atmospheric pressure, as the treatment, which is provided in a hyperbaric chamber and hence known as hyperbaric oxygen therapy (HBOT). Resultant augmented oxygen levels in the blood (hyperoxemia) and tissue (hyperoxia) increase the bioavailability of oxygen (hyperoxygenation), which permits its therapeutic applications not only owing to its utility in hypoxic conditions with diffusibility but also for its antimicrobial, immunomodulatory, and angiogenic properties. The considerable usage of HBOT to treat decompression sickness during World War II, encouraged further research and application. Currently, HBOT is well established both as a primary and as an adjunctive therapy. It is considered the mainstay of management in several potentially life-threatening conditions such as carbon monoxide poisoning, decompression illness, and gas embolism. HBOT is considered an adjunctive therapy in chronic conditions such as non-healing wounds. Recently, HBOT was utilized during the COVID-19 pandemic, which has shed light on the research in the field of HBOT. Further studies are yet to widen the horizon of HBOT as an option in systemic and inflammatory conditions and in the field of cancer, while minimizing the known adverse effects of HBOT.