A Celtic festival!
october

Halloween is an ancient Celtic festival.The Celtic New Year
fell on November 1.They believed that ghosts and demons
woul come to earth from the underworld on the last day of
the year.So,on October 31,people lit great bonfires to
frighten them away.
In many places of Britain and Ireland,the traditions of
ghosts and witches,games and bonfires continued and spread
to the USA,and more recentlyto some places in Brazil as well.
One of the most popular Halloween games is the "trick or treat",
in whitch children knock on doors to ask for a treat and sometimes
play a trick if they do not get a treat.