Floating-point numbers are a way to represent real numbers in computing, allowing for a wide range of values. They consist of three parts: a sign (indicating positive or negative), an exponent (which scales the number), and a fraction (or mantissa) that contains the significant digits. This format enables computers to handle very large or very small numbers efficiently. In programming, floating-point numbers are commonly used for calculations that require precision, such as scientific computations or graphics rendering. However, they can introduce rounding errors due to their limited precision, which is important to consider when performing arithmetic operations.