Β (Beta) is the second letter of the Greek alphabet, following Α (Alpha). In the Greek numeral system, it has a value of 2. The letter is often used in various fields, including mathematics and science, to represent variables or coefficients. In finance, Β (Beta) measures the volatility of an asset or portfolio in relation to the overall market, indicating its risk level. A Beta greater than 1 suggests higher volatility than the market, while a Beta less than 1 indicates lower volatility. This concept is crucial for investors assessing potential risks and returns.