Pronunciation:
Sarvesham svastir bhavatu | sarvesham shantir bhavatu | sarvesham purnam bhavatu | sarvesham mangalam bhavatu

Translation:
May there be well-being for all,
May there be peace for all.
May there be wholeness for all,
May there be happiness for all.

Why chant it:
Om is said to be the first sound heard at the creation of the universe. When each syllable is pronounced fully, you should feel the energy of the sound lifting from your pelvic floor all the way up through the crown of your head. The droning sound of the Om is said to unblock the throat chakra, which can lead to more attuned communication with others.