Microsoft C/C++ supports three floating-point types that conform to the Institute of Electrical and Electronics Engineers (IEEE) standard 754 format:
Type float, a 32-bit floating-point quantity
Type double, a 64-bit floating-point quantity
Type long double, an 80-bit floating-point quantity (not supported in the alternate math package)
You can declare variables as any of these types. You can also declare functions that return any of these types.