Candela is a unit of measurement used to quantify the intensity of light emitted from a source in a specific direction. It is one of the seven base units in the International System of Units (SI) and is crucial for understanding how bright a light source appears to the human eye. The term "candela" comes from the Latin word for candle, reflecting its historical use as a standard for measuring light. In practical terms, the candela helps in various fields, including photography, theater lighting, and interior design, where proper lighting is essential. It allows designers and engineers to create environments that are visually appealing and functional by ensuring adequate illumination levels for different settings.