This is a Mexican tradition comprising 9 days celebrated along the Christmas Eve. (From December 16th to December 24th). (*celebrated along in Mexico, Guatemala and parts of theSouthwestern United States)
Las Posadas were created by a friar named Diego Soria, who requested the authorization to the pope to let them celebrate the birth of Jesus Christ as the true sun and light of the world and represent in a theatrical way the peregrination of Maria & José.
Regularly these meetings are celebrated in different houses, where the respective owners receive all the people who also are celebrating the arrival of Jesus Christ to Belem.
It is well known that there is a schedule for every posada and its respective day. First of all, everybody have to sing different kind of songs typical for the Christmas Eve that emulate the joy of the birth of JC. Then and they have to pray in four different times:
1. The daily pray, when the thanks for the glorious day
2. A pray for Maria
3. A pray for José
4. Finally, a pray according to the day they are. (At the end, will be 9 different prayers.)
At the end they pray just a little more and break a piñata that represents the fight of the mankind against the devil and the capital sins. (The seven peaks in the piñata).
Finishing the piñata they use to sing and feel the joy of the new king and the respective owner of each house has to give to all his visitors a traditional drink made by fruits of the respective season of the Christmas (Ponche de frutas) and little gifts to the children (given in a bag shape) with fruits and candies, sometimes they also give inoffensive sparklers and fireworks.
On the other hand every none religious party celebrated among the 16th and 24th of December has created some kind of disagreements with some catholic groups who think that those are not posadas, instead of those are parties, and that is not the idea/meaning of the original posadas.