The Degree Celsius (°C) is the internationally recognized unit for measuring temperature, defined as one‑hundredth of the interval between the freezing and boiling points of water at standard atmospheric pressure; it quantifies thermal energy in everyday life, weather forecasts, industrial processes, and scientific research, making it essential for accurate climate monitoring, laboratory experiments, and engineering calculations, while its simple, linear scale and universal symbol (°C) ensure clear communication across global standards and practical applications.