17th of Tammuz
The 17th day of the Jewish month of Tammuz is a day of mourning to mark the anniversary of five calamities that befell the Jewish people. It is known as the Fast of Shiva Asar B'Tammuz.
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AM and PM Explained
How does the 12-hour clock system work? Is midnight 12 am or 12 pm?
Tisha B'Av
Tisha B' Av is a Jewish day of prayer and fasting. It is observed on the ninth day of the month of Av in the Jewish calendar. It commemorate the anniversary of five calamities, including the destruction of the First Temple and the Second Temple.
Daylight Saving Time (DST)
Why do many countries set the clocks back and forth an hour twice a year?