You see them every day of the week – including Shabbos and Yom Tov, and at all times of the day and night; dashing out of their homes, shops and shuls in order to perform acts of chesed (good deeds). They interrupt participation in joyous family simchas (celebrations) and even when davening (praying) to Hashem (G-d) during the most serious days of the Jewish calendar (Rosh Hashana and Yom Kippur), in order to try and save the life of another human being. In many cases, they do not even know who that person is.