Hex is short for hexadecimal.
Except for the fact that hex means 6 while hexadecimal means 16. It's one of the worst thought out shortenings since they turned automobile into auto.
Except in context hexadecimal is used exclusively when relating to computer technology so there would never be confusion in that regard and the name for the base six number system is senary anyway.
It's only proper to be snide when you are correct.