Excuse me, what is this symbol posted on the door frame for? Is it useful?

It is used to warm the town house. Chaoshan people usually use it to keep peace, not to exorcise ghosts and evil spirits, so don't worry. Besides, the immortals in Chaoshan don't know you, hahahaha, but you can tear it off and burn it, because generally we don't throw things related to immortals directly into the trash can, but they are usually incinerated. The location of the indoor door is exquisite ~ the door is the entrance and exit of the building and the face of the house. A clean and tidy home will naturally be respected by the outside world. Luxury houses are favored precisely because all luxury houses have a unique door. Sticking a symbol can alleviate the suffocation of rushing to the gate outside the house; Secondly, it can prevent the exuberant leakage of the house; Thirdly, participants in sports can calm down and adjust their breath, which will directly improve the wealth of the house and make money.