扶乩又叫扶鸞，是一種古代的占卜術，扶乩始於何時，頗難稽考。
如圖所示，當乩筆在沙盆裡的沙上書寫時的過程便稱 " 扶乩 " 。
書寫在沙上的文字叫 " 乩文 " 。
在神壇前，當乩手 ( 通常是一位有此功能的道侶 ) 扶著乩筆，為祈求者向仙師請求，乩筆會自動移動，在沙上的乩字多屬草書，要由乩手或在旁看字的 " 判讀生 " 宣讀，再由 " 記錄生 " 筆錄在乩冊 ( 又稱鸞冊 ) 內，在停乩後，作乩手的必須翻看乩冊，以確定乩文正確無訛，方由 " 記錄生 " 繕寫，交與叩問的人。跟據乩文的解釋，便可獲得仙師的指示和意思。
( Translation )
The process of writing some characters with a divine tool on the sand inside the divine pot as shown is termed as " Fu Ji ".
The writing on the sand is termed as the inscription of " Fu Ji ".
At the font of a altar, holding the rack, someone ( normally a speical Toaist priest ) consults a fairy for his client, a divine tool ( fairy's stationery ) will move automatically on the sand inside the divine pot. During the process of " Fu Ji ", he or a member of his team reads the inscription of " Fu Ji " loudly. Then the other person jots it down in the book called " Inscription of Fu Ji ". When the process of " Fu Ji " stops, the record of inscription has to be confirmed by the " Fu Ji " operator. Then a true copy of the inscription of " Fu Ji " written on the paper will be given to his client. One ( normally a speical Toaist priest ) can get the directions / meanings from the fairy through the explanation of the inscription of " Fu Ji ".
Of course, the prescription of herbs for curing illness or the description of the happening in future will be obtained.
Note :
Not everyone can perform "Fu Ji " process
and / or understand the inscription of " Fu Ji ".