What is a kiss???

What is a kiss???
In view of………..
(1)Geometry…
“KISS IS THE SHORTEST DISTANCE BETWEEN 2 LIPS!”

(2)Economics…
“KISS IS THAT THING FOR WHICH DEMAND IS ALWAYS HIGHER THAN SUPPLY!”

(3)Physics…
KISS IS THE PROCESS OF CHARGING A HUMAN BODY!”

(4)Computer…
“KISS IS LIKE A LAN, IN WHICH 2 BODIES ARE CONNECTED WITHOUT ANY DATA CABLE!”