K- is a letter in the Latin alphabet, commonly used in various languages. It is the 11th letter and represents a voiceless velar plosive sound, as in the word kite. In the context of grading systems, a "K" can indicate a kindergarten level, often used in educational settings to denote early childhood education. In mathematics, "K" often represents a constant or a variable in equations. Additionally, in the realm of chemistry, "K" is the symbol for potassium, an essential element for living organisms. It plays a crucial role in various biological processes, including nerve function and muscle contraction.