Yom HaAtzmaut marks the anniversary of the establishment of the modern state of Israel in 1948. It is observed on or near the 5th of the Hebrew month of Iyar on the Jewish calendar, which usually falls in April (this year, in May).
The Israeli Knesset (parliament) established the day that precedes Yom HaAtzmaut as Yom HaZikaron, a day to memorialize soldiers who lost their lives fighting in the War of Independence and subsequent battles, as well as a day to remember civilian victims of terrorism.