Gcal is a program for calculating and printing calendars. Gcal displays hybrid and proleptic Julian and Gregorian calendar sheets, respectively, for one month, three months or a whole year. It also displays eternal holiday lists for many countries around the globe, and features a very powerful creation of fixed date lists that can be used for reminding purposes. Gcal can calculate various astronomical data and times of the Sun and the Moon for at pleasure any location, precisely enough for most civil purposes. Gcal supports some other calendar systems, for example the Chinese and Japanese calendar, the Hebrew calendar and the civil Islamic calendar, too.