Why we Hiccups?

The reason we hiccup is unknown.The technical term for hiccups is singultus (from the Latin, singult, which describes catching your breath while crying). Hiccupping is a complex reflex: A sudden contraction or spasm of the diaphragm and the muscles between the ribs makes you inhale quickly and involuntarily.
Nerves inside the chest send signals to the diaphragm and muscles between the ribs to spontaneously contract during normal breathing. This “hiccup reflex” may be set off by many triggers, including:
Emotional stress or excitement
Stretching of the stomach as may occur after overeating, drinking carbonated beverages, or swallowing air
Abrupt changes in the temperature (as with drinking a hot beverage)
Alcohol binging
Smoking