The 126.96.36.199 version of Hebrew Calendar is provided as a free download on our website. Our antivirus check shows that this download is clean. Hebcal9.exe is the most frequent filename for this program's installer. The actual developer of the free program is Calendar Maven. The most popular versions among Hebrew Calendar users are 9.1 and 9.0. Hebrew Calendar lies within Internet & Network Tools, more precisely Browser plugins.
From the developer:
The Hebrew calendar has evolved over time. For example, until the Tannaitic period, the months were set by observation of a new crescent moon, with an additional month added every two or three years to keep Passover in the spring, again based on observation of natural events, namely the ripening of the barley crop, the age of the kids lambs and doves, the ripeness of the fruit trees, and the relation to the Tekufah (seasons.) Through the Amoraic period and into the Geonic period, this system was displaced by mathematical rules. The principles and rules appear to have been settled by the time Maimonides compiled the Mishneh Torah in the 12th century.
You may want to check out more software, such as Live Mail Calendar Converter, Export Live Mail Calendar to Outlook or Lady's Calendar, which might be related to Hebrew Calendar.