What was the blitzkrieg and why was it so effective during the war?

The blitzkrieg was a military act where forces would attack the enemy quickly and forcefully and then encircle them. It was very effective during the war because there were many surprise blitzkrieg operations, the enemy was substantially less prepared and it is much harder to react to an offense swiftly if you are caught off guard. It is now known that blitzkrieg was not an actual military idea that was carried off, more that it was just an offense, but Western European newspapers sensationalized it.