CHAI: This incredible photo was taken in Nahariya, Israel…notice the two Hebrew letters (Chet, Yud) that appear in the sky

Chai (חי) is the Hebrew word for life. The word, consisting of two Hebrew letters —chet (ח) and yud (י)— is a Jewish symbol, frequently appearing on pendants and other jewelry.

Unlike the Indian tea chai, which is pronounced with the “ch” sound of “chocolate,” the Hebrew chai is pronounced with the same “kh” sound as in challah. Both words rhyme with “high,” however.

Chai also refers to the number 18. That’s because each Hebrew letter has a numerical equivalent, and the sum of chet (numerical value of 8) and yud (numerical value of 10) is 18. As a result of its connection to the word for life, the number 18 is considered a special number in Jewish tradition. For this reason, Jews frequently make gifts or charitable contributions in multiples of $18. (My Jewish Learning)