What the purpose for using Zhaojian/Zhaoban? And how we use it?

This tablet is called the Petition Tablet, in chinese, pronounce as Hu (笏) or Zou Ban (奏板).

In the ancient time, when Officers attending meeting or seeking permissions from Emperor, they will need to hold onto this tablet and make their requests or petitions.

In the modern days now, our Priests will use them during Rituals.