The built-in functions that make up FormCalc cover a wide range of areas, including mathematics, dates and times, strings, finance, logic, and the web. These areas represent the types of functionality that typically occur in forms, and the purpose of the functions is to provide quick and easy manipulation of form data in a useful way.At the most basic level, a calculation can consist of only a single FormCalc function. However, a single FormCalc function can make use of other FormCalc functions as parameters.