实用万年历是一款比较实用的多功能日历。日期计算等均采用了现代高精度天文算法。日期范围：从公元前4600年至公元10000年，历时近一万五千年。-Practical calendar is a more practical multifunctional calendar. Date all adopts the modern high-precision astronomical algorithms. Date range: from 10,000 BC to AD 4600, lasted nearly fifteen thousand years.