Threshold

A threshold is a point of entry or beginning, often referring to a level or point at which something happens or changes. In physical terms, it is the bottom edge or sill of a doorway, serving as a boundary between two spaces. Metaphorically, it signifies a point of entry or transition, such as the threshold of an era or the threshold of pain. The term originates from the Old English þrescwold, meaning "a door sill." In Hebrew, the word for threshold is סף (saf). In other languages, it is known as seuil in French, Schwelle in German, and umbral in Spanish. Thresholds are significant in various contexts, including physics, where it refers to the minimum level needed to produce a certain effect, and in computing, where it denotes a point at which a certain condition is met, triggering a process or event.