Date and time calculations are important in many software applications, yet C++03 had limited support for manipulating dates and performing calculations with them. The Boost Date Time library provides a set of intuitive interfaces for representing dates, timestamps, durations, and time intervals. By allowing simple arithmetic operations involving dates, timestamps, durations, and supplementing them with a set of useful date/time algorithms, it enables fairly sophisticated time and calendar calculations using little code.
The Gregorian calendar, also known as the Christian calendar, was introduced by Pope Gregory XIII in February 1582 and over the next few centuries, replaced the Julian calendar in the vast majority of the western world. The Date_Time library provides a set of types for representing dates and related quantities: