Question: What should everyone (and not just Jews) know about Yom Kippur?
Answer: Yom Kippur (as all Jewish Holiday) has a deep, symbolic meaning beyond traditions and religious observance.
It is not a specific day, but a unique state when we judge ourselves on where we are, after honest self-examination (symbolized by the month of Elul) we make a decision to start anew (symbolized by Rosh HasHanah) in order to achieve our Human purpose: to become similar (Human=Adam=similar) to Nature’s singular, governing and life giving force, principle – selfless, altruistic, unconditional service and love of others.
This is the principle – based on nature’s most fundamental law of keeping life giving and sustaining balance and homeostasis – that is poetically in an archaic way expressed in the commandment of “Love Thy Friend as Thyself”, which is the single most important commandment of the Torah (Instruction Guide to Reality).
Additionally from Jewish point of view it is also the time of examination, “self-judgement” how much we Jews fulfill our historic national mission of teaching all the above to others as “Light unto others”. As long as we escape this role with all the usual excuses we are like Jonah the prophet, who also was not even allowed to die, disappear – just like Jews through history – until he overcame his resistance and at the end fulfilled his given mission.
The real “blowing off the Shofar” is starting this important historic Jewish mission!