How does a bullet shot from a gun kill a person INSTANLY??

I do search forum..many factors included:

1) Bullet caliber
2) distance
3) What kind of gun in use.
4) Impact of the bullets.

I'm curios about this problem...why?????

& dun ask me why asking this question...

cos just curiosity & want to learn it....(note: this is an scientific & biology issue "or" it maybe something that cannot explain by science?? )

PLs dun post something like this: "when u die u know lo"... (appreciate for good comment )

Anyway thank u for viewing.

Depends on your definition of instantly.

Human are technically still alive for a short moment prior to brain/heart malfunction. The same issue is plaguing death penalty legislator in their quest to find a execution method where death arrives faster than the sensation of pain/trauma.